find the DB =[tex]\displaystyle\bf \sqrt{17^2-8^2} =15[/tex] ; now find AD=AB-DB=21-15=6 .Then AC=[tex]\displaystyle\bf \sqrt{AD^2+CD^2} =\sqrt{6^2+8^2} =10[/tex]
Answer:
C
Step-by-step explanation:
Using Pythagoras' identity in both right triangles
To find BD
BD² + CD² = BC²
BD² + 8² = 17²
BD² + 64 = 289 ( subtract 64 from both sides )
BD² = 225 ( take the square root of both sides )
BD = [tex]\sqrt{225}[/tex] = 15
Then
AD = AB - BD = 21 - 15 = 6
To find AC
AC² = AD² + CD²
AC² = 6² + 8² = 36 + 64 = 100 ( take the square root of both sides )
AC = [tex]\sqrt{100}[/tex] = 10 → C
Do you think there’s sufficient evidence in the article to conclude that bright red leaves in the fall help protect the trees in the winter? Explain your answer.
From online research, the article is;
As days get shorter and colder in the autumn, chlorophyll molecules break down. Leaves quickly lose their green color. Some leaves begin to look yellow or orange because they still contain pigments called carotenoids. One such pigment, carotene, gives carrots their bright-orange color.
But red is special. This brilliant color appears only because the leaves of some plants, including maples, actually produce new pigments, called anthocyanins.
That’s a strange thing for a plant to do without a reason, says Bill Hoch of the University of Wisconsin in Madison. Why? Because it takes a lot of energy to make anthocyanins.
Why red?
To figure out the purpose of the red pigment, Hoch and his coworkers bred mutant plants that can’t make anthocyanins and compared them with plants that do make anthocyanins. They found that plants that can make red pigments continue to absorb nutrients from their leaves long after the mutant plants have stopped.
This study and others suggest that anthocyanins work like a sunscreen. When chlorophyll breaks down, a plant’s leaves become vulnerable to the sun’s harsh rays. By turning red, plants protect themselves from sun damage. They can continue to take nutrients out of their dying leaves. These reserves help the plants stay healthy through the winter.
The more anthocyanins a plant produces, the redder its leaves become. This explains why colors vary from year to year, and even from tree to tree. Stressful conditions, such as drought and disease, often make a season redder.
Now, Hoch is breeding plants for a new set of experiments. He wants to find out whether turning red helps plants survive cold weather.
“There’s a clear correlation between environments that get colder in the fall and the amount of red produced,” he says. “Red maples turn bright red in Wisconsin. In Florida, they don’t turn nearly as bright.”
More protection
Elsewhere, scientists are looking at anthocyanins in other ways. A recent study in Greece, for instance, found that as leaves grow redder, insects eat them less. On the basis of this observation, some scientists argue that red pigments defend a plant against bugs.
Leaves may turn red in the autumn to protect themselves from the sun’s ultraviolet rays.
J. Miller
Hoch rejects that theory, but Lee thinks that it might make sense. He points out that red leaves contain less nitrogen than green ones do. “It may actually be that insects avoid red leaves because they’re less nutritious,” Lee says.
However, “it’s pretty confusing at this point,” Lee admits. “People debate back and forth.”
To settle the debate, scientists will need to look at more species under more conditions, Lee says. So, he’s now researching leafy plants rather than trees. He’s especially interested in tropical plants, whose leaves turn red when they’re young rather than old.
Answer:
As seen in the Explanation, different people have given reasons why bright red leaves in the fall help protect the trees in the winter. Thus, there is sufficient evidence to conclude that bright red leaves in the fall help protect the trees in the winter.
Step-by-step explanation:
From the article, we can see that Hoch and his coworkers carried out an experiment on mutants and they discovered that plants that can make red pigments tend to continue absorbing nutrients from their leaves a long time after the mutant plants have stopped.
This study and other believe that plants make anthocyanins which acts as a kind of sunscreen to the plants. They also discovered that by the plants turning red, they protect themselves from sun damage
Also, we see that some scientists in Greece found out that as leaves grow redder, insects eat them less and they argued that red pigments defend a plant against bugs and as such Leaves may turn red in the autumn to protect themselves from the sun’s ultraviolet rays.
My Answer: One study said that anthocyanins are pigments that make leaves turn red. And some trees don’t absorb as many nutrients as trees with red leaves. That particular study focused on trees that don’t produce anthocyanins. So i believe there's some evidence, but not a definitive conclusion.
Edmentum Answer: There’s some evidence, but not a definitive conclusion. One study focused on trees that don’t produce anthocyanins. Anthocyanins are pigments that make leaves turn red. The study said that these trees don’t absorb as many nutrients as trees with red leaves.
Another study found that insects are generally not inclined to eat red leaves on trees. There seems to be a trend that suggests that red leaves are important for the trees’ survival in the fall. This trend needs to be validated by conducting more tests.
Step-by-step explanation:
Paraphrased
Which is the largest three-digit number of the form 9k + 1, where k is any positive integer?
Answer:
991
Step-by-step explanation:
We are looking for a number that is one more than a multiple of 9(denoted by the 9k) and is a three digit number. We can start by looking for 3-digit number divisible by 9 which are close to 1,000, since that is the next number larger than the largest three-digit number. We can tell that 999 is divisible by 9 because when divided it does not leave a remainder(you can also figure this out with divisibility tricks). We add one to get 1,000. This is not a three-digit number, so we need to look for a smaller multiple of 9. Subtracting 9 from 999, we get the next largest multiple of 9. We can add 1, and this time, the number, 991, is a three digit number, and the largest that can be in the form 9k + 1.
PLEASE HELP! Use the graph to solve the system of equations.
A. (-5,0)
B. (0,5)
C. (0,0)
D. (2,3)
Answer:
D
Step-by-step explanation:
Look for the intersection point of the two graphs
Another way:
You can just substitute each pair in both equations and u will find that d is the correct answer
Someone tell me where everyone is going right please !!
Answer:
A 2
B 1
C 4
D 3
Step-by-step explanation:
( ) means not including (also used for infinity)
[ ] means including
The answer choices are in interval form, showing all the possible answer choices between two numbers and if the answer choice includes or excludes a number using the () []
Explanation for A:
x < 7.8 means x won't include 7.8 since the symbol is "less than" and not "less than or equal to".
x can be anything, it just has to be less than 7.8, so the answer is:
2 (-infinity, 7.8)
Explanation for B:
x <= 7.8 means x will include 7.8 since the symbol means "less than or equal to".
x can be anything, it just has to be less than or equal to 7.8, so the answer is:
1 (-infinity, 7.8]
Explanation for C:
x >= 7.8 means x will include 7.8 since the symbol means "greater than or equal to".
x can be anything, it just has to be greater than or equal to 7.8, so the answer is:
4 [7.8, infinity)
Explanation for D:
x > 7.8 means x won't include 7.8 since the symbol means "greater than" and not "greater than or equal to".
x can be anything, it just has to be greater than 7.8, so the answer is:
3 (7.8, infinity)
Hope it helps (●'◡'●)
Answer:
A:2 B:1 C:4 D:3
Step-by-step explanation:
18 - (-f) = 91 (With work please)
18 - (-f) = 91
Subtracting a negative value changes to addition:
18 + f = 91
Subtract 18 from both sides:
F = 73
Answer:
f = 73
Step-by-step explanation:
Solve for f
18 - ( - f ) = 91
Remove the parantheses and change their sign.18 + f = 91
subtract each side by 1818 - 18 + f = 91 - 18
calculatef = 73
prime numbers that can be expressed as a sum and difference of 2 prime numbers
ASAP
Given:
Prime numbers can be expressed as a sum and difference of 2 prime numbers.
To find:
The prime numbers that can be expressed as a sum and difference of 2 prime numbers.
Solution:
Prime numbers are the positive integers which are greater than 1, divisible by only 1 and itself.
Prime numbers are 2, 3, 5, 7, 11, 13, 17, 19,... .
Only 2 is the even prime number.
The sum and difference of two odd integers is always an even number. So, we need to take one even prime number and one odd prime number to add and subtract the numbers to get a prime number.
[tex]2+3=5[/tex]
[tex]7-2=5[/tex]
Therefore, 5 is the only prime number that can be expressed as a sum and difference of 2 prime numbers.
the area of a circle is 616 m square find the radius 5 equals to 22/7
Step-by-step explanation:
[tex]here \: is \: your \: solution : - \\ \\ GIVEN \: \: -:- \\ \\ = > \: area \: of \: circle \: = 616 \: m {}^{2} \\ \\ \ = > pi = 22 \div 7 \\ \\ = > we \: need \: to \: find \: radius \: \\ \\ = > area \: of \: circle \: = \pi \: r {}^{2} \\ \\ = > \: \pi \: r {}^{2} = 616 \: m {}^{2} \\ \\ = > \: r {}^{2} \times (22 \div 7) = 616 \\ \\ = > \: r {}^{2} =( 616 \times 7) \div 22 \\ \\ = > \: r { }^{2} = 4312 \div 22 \\ \\ = > r {}^{2} = 196 \\ \\ = > \: r = \sqrt{196} \\ \\ = > \: r = 14 \: \: \: (ANSWER✓✓✓) \\ \\ HOPE \: IT \: HELPS \: YOU \: (◕ᴗ◕✿)[/tex]
If the volume of a cubical room is 2700 cm^3 . Find its length
Step-by-step explanation:
If the volume of a cubical room is 2700 cm³ .
l³=2700
l=3 (100)⅓
Find the greatest common factor of the
following monomials:
36m3n4. 2m5n3. 4m6n6
Answer:
2m^3n^3
Step-by-step explanation:
Let us start with the number parts
36 , 2 and 4
2 is common here as it can divide all
The smallest m factor is m^3 so it is common for all
The smallest n factor is n^3 which is also common for all
So, we have the greatest common factor as;
2 * m^3 * n^3 = 2m^3n^3
find area of the figure
thanks for any help
Answer:
8050 m²
Step-by-step explanation:
We can divide the diagram up into two components: a rectangle with a width of 60 m and a height of 80 m, and a triangle with a base of 130 m (190 - 60) and a height of 50 m (80 - 30).
The area of the rectangle:
A = lw
A = 60 m (80 m)
A = 4800 m²
The area of the triangle:
A = 1/2 b*h
A = 1/2 (130 m) (50 m)
A = 1/2 (6500 m²)
A = 3250 m²
Now, we can add the areas of the two separate components:
A = 4800 m² + 3250 m²
A = 8050 m²
How to solve the area of a triangle
Step-by-step explanation:
The photo which is in the attachment is an example for your question. hope this answer helps you!!In a geometric progression, the first tern is 81 and the fourth term is 24. find the common ratio
Step-by-step explanation:
81/24= 27/8Hello,
Let's say a the first term and r the ratio of the G.P.
[tex]u_1=a=81\\u_2=a*r\\u_3=a*r^2\\u_4=a*r^3\\\\\dfrac{u_4}{u_1} =\dfrac{a*r^3}{a} =r^3=\dfrac{24}{81} =\dfrac{8}{27} \\\\r=\sqrt[3]{\dfrac{8}{27} } \\\\\boxed{r=\dfrac{2}{3}}\\[/tex]
2.
What is the difference between the lower quartile rainfall of Florida and the lower quartile rainfall of Pennsylvania?
Answer:
0.5 inches
Step-by-step explanation:
The lower quartile is the value on the left side of the box plot
lower quartile for Florida = 3.5 inches
lower quartile for Pennsylvania = 3 inches
difference = 3.5 - 3 = 0.5 inches
Please help I suck at dividing Fractions (Will give brainliest)
Answer:
The final result is 7/10
the "divisions" (divisor) is 1/10
thus the answer is 7/10 ÷ 1/10
the actual operation ....
"to divide fractions we INVERT and Multiply"
7/10 * 10/1 = 70/10 = 7
there are 7 arrows going to the right
Step-by-step explanation:
Someone please help me with this math problem?
HELP ME !
Please!
Which of the following tables represents a function?
What are the different forms of a quadratic function and what do the variables represent?
Answer:
Quadratic equations of second degree.
[tex]{ \bf{a {x}^{2} + bx + c = 0}}[/tex]
Quadratic equations of third degree.
[tex]{ \bf{a {x}^{3} + {bx}^{2} + cx + d = 0}}[/tex]
The mass, m grams, of a radioactive substance, present at time t days after first being observed, is given by the formula m=24e^-0.02t. Find
(i) the value of m when t=30.
(ii) the value of t when the mass is half of its value at t=0.
(iii) the rate at which the mass is decreasing when t=50.
Answer:
(i) The value of m when t = 30 is 13.2
(ii) The value of t when the mass is half of its value at t=0 is 34.7
(iii) The rate of the mass when t=50 is -0.18
Step-by-step explanation:
(i) The m value when t = 30 is:
[tex] m = 24e^{-0.02t} = 24e^{-0.02*30} = 13.2 [/tex]
Then, the value of m when t = 30 is 13.2
(ii) The value of the mass when t=0 is:
[tex] m_{0} = 24e^{-0.02t} = 24e^{-0.02*0} = 24 [/tex]
Now, the value of t is:
[tex] ln(\frac{m_{0}/2}{24}) = -0.02t [/tex]
[tex] t = -\frac{ln(\frac{24}{2*24})}{0.02} = 34.7 [/tex]
Hence, the value of t when the mass is half of its value at t=0 is 34.7
(iii) Finally, the rate at which the mass is decreasing when t=50 is:
[tex] \frac{dm}{dt} = \frac{d}{dt}(24e^{-0.02t}) = 24(e^{-0.02t})*(-0.02) = -0.48* (e^{-0.02*50}) = -0.18 [/tex]
Therefore, the rate of the mass when t=50 is -0.18.
I hope it helps you!
Need help on this question asap please
Answer:
8 m
-----------------Work--------------
2*3 = 6
Ratio
2*4 = 8
Kathy travels in a taxi which charges $ 5.75 flat rate in addition to $ 2.50 per mile. Kathy has only $25 in her wallet. How many miles can Kathy travel without exceeding her limit?
HELPP
Answer: 7.7 miles
Step-by-step explanation:
2.5x + 5.75 = 25 (x = each mile traveled)
2.5x = 25 - 5.75
2.5x = 19.25
x = 7.7 miles
simplify 9×(-5)×(-6)×3
Answer:
810
Step-by-step explanation:
(-5)×(-6) = 30
9*3 = 27
27*30 = 810
Please help me I really can't do these
Answer:
[tex]110 in^{2}[/tex]
Step-by-step explanation:
[tex]===========================================[/tex]
Formulas:
Area of a rectangle/square:
[tex]A=lw[/tex]
[tex]===========================================[/tex]
Squares(2):
5*5=25
Multiply by 2
50 in.
Rectangles(4):
5*3=15
Multiply by 4.
60 in.
Total:
Add.
50+60= 110 in2
I hope this helps!
The pie chart represents the results when 120 people in a shopping centre were asked which country they were born in. Uk:84 What fraction of people were born in the UK? Give your answer in its simplest form.
Answer:
22 people were born in the uk (66 ÷ 360) × 120=22
Step-by-step explanation:
Using the pie chart, the fraction of people born in the UK, is: 7/30.
What is a Pie Chart?A pie chart is a graphical representation used to describe the composition of a data using degrees or percentages.
84° is given as the number of people that were born in the UK.
That's about: 84/360 × 120 = 28 people.
28 out of 120 people would give us a fraction of: 28/120 = 7/30.
Learn more about pie chart on:
https://brainly.com/question/26851221
#SPJ2
Helpppppp and explain tooo thank you :)
Answer:
{5, 6, 7}
Step-by-step explanation:
When we have a given relation, the domain is the set of inputs, and the range as the set of the outputs.
so for a function f(x), and a domain {a. b. c}
The range is:
{f(a), f(b), f(c)}
In this case, we have:
f(x) = x + 6
and the domain is {-1, 0, 1}
Then the range is:
{ f(-1), f(0), f(1) }
{-1 + 6, 0 + 6, 1 + 6}
{5, 6, 7}
The correct option is the third one.
Please help ASAP...will give brainliest
Answer:
The answer is 90cm
Step-by-step explanation:
Hello,
Lateral area = (3+3+3+3)*6=4*3*612*6=72 (cm²)
Bases area= 2*3²=18 (cm²)
Total area= 72+18=90 (cm²)
Prove: AAB
Step
Statement
Reason
Given
1
ABCD is a parallelogram
ABCD
Select a Reason!!
2
A
B
N
simplify the ratio 4.5: 3 1/2 in its simplest form
Answer:
9 : 7
Step-by-step explanation:
Given
4.5 : 3 [tex]\frac{1}{2}[/tex] ( multiply both parts by 2 to clear the fractions )
= 9 : 7
Someone pls help me ill give out brainliest pls don’t answer if you don’t know
Answer:
y < -7
Step-by-step explanation:
You balance it like a normal equation:
8y + 3 > 15y + 52
8y + 3 (-8y) > 15y + 52 (-8y)
3 (-52) > 7y + 52 (-52)
-49 (÷7) > 7y (÷7)
y < -7
Max earned $8 for each hour of work he completed. His mom put $120 in his savings account at the end of the summer. By the end of the summer, Max had $400 in his savings account. Write an equation to determine the number of hours Max worked over the summer.
Answer:
8x +120= 400
Step-by-step explanation:
Let the number of hours Max worked over the summer be x.
Assuming that he had $0 in his bank at the start of summer,
Total savings= 8(number of hours) +120
400= 8x +120
8x +120= 400
To find the value of x, first bring all the constants to one side of the equation.
8x= 400 -120
Simplify:
8x= 280
Divide both sides by 8:
x= 280 ÷8
x= 35
∴ Max worked for 35 hours over the summer.
yall still in school? i ended may 27th hbu?
Answer:
mine ended june 9th but i got summer school for 2 classes lol
School ended the 15 of June but I'm in summer school rn it ends this Friday