Given:
The x- intercepts of a parabola are (0,-6) and (0,4).
The parabola crosses the y- axis at -120.
Lucas said that an equation for the parabola is [tex]y=5x^2+10x-120[/tex] and that the coordinates of the vertex are (-1, -125).
To find:
Whether Lucas is correct or not.
Solution:
The x- intercepts of a parabola are (0,-6) and (0,4). It means (x+6) and (x-4) are the factors of the equation of the parabola.
[tex]y=a(x+6)(x-4)[/tex] ...(i)
The parabola crosses the y- axis at -120. It means the equation of the parabola must be true for (0,-120).
[tex]-120=a(0+6)(0-4)[/tex]
[tex]-120=a(6)(-4)[/tex]
[tex]-120=-24a[/tex]
Divide both sides by -24.
[tex]\dfrac{-120}{-24}=a[/tex]
[tex]5=a[/tex]
Substituting [tex]a=5[/tex] in (i), we get
[tex]y=5(x+6)(x-4)[/tex]
[tex]y=5(x^2+6x-4x-24)[/tex]
[tex]y=5(x^2+2x-24)[/tex]
[tex]y=5x^2+10x-120[/tex]
So, the equation of the parabola is [tex]y=5x^2+10x-120[/tex].
The vertex of a parabola [tex]f(x)=ax^2+bx+c[/tex] is:
[tex]Vertex=\left(-\dfrac{b}{2a},f(-\dfrac{b}{2a})\right)[/tex]
In the equation of the parabola, [tex]a=5,b=10,c=-120[/tex].
[tex]-\dfrac{b}{2a}=-\dfrac{10}{2(5)}[/tex]
[tex]-\dfrac{b}{2a}=-\dfrac{10}{10}[/tex]
[tex]-\dfrac{b}{2a}=-1[/tex]
Putting [tex]x=-1[/tex] in the equation of the parabola, we get
[tex]y=5(-1)^2+10(-1)-120[/tex]
[tex]y=5-10-120[/tex]
[tex]y=-125[/tex]
So, the vertex of the parabola is at point (-1,-125).
Therefore, Lucas is correct.
35. What is the point-slope form of the
equation for the line with a slope of
-2 that passes through (1,4)?
A. y + 1 = -2(x + 4)
B. y - 1 = -2(x - 4)
C. y + 4 = -2(x + 1)
D. y - 4 = -2(x - 1)
Answer:
D) y - 4 = -2 ( x - 1 )
Step-by-step explanation:
Point-slope form is y - y₁ = m ( x - x₁ )
so you just plug in your points, hope this helped
Check all that apply
Answer:
all of them are REAL numbers
1. is also RATIONAL
2. is also IRRATIONAL
3. is also IRRATIONAL
4. is also NATURAL, WHOLE, INTEGER and RATIONAL
5. is also INTEGER and RATIONAL
6. incorrect, because integer is just the whole numbers extended by their additive counterparts (the negative natural numbers). in other words, their absolute values are whole numbers. 5.5 as well as -5.5 are not fitting that criteria.
7. incorrect, because this pattern does not fit the definition of a radical number, where the number eventually begins to repeat the same finite sequence of digits over and over. in this example the pattern is not based on a finite sequence of digits.
Can someone explain this
=========================================================
Explanation:
Let x be the unknown angle we want to find. This angle is in degrees.
The diagram shows 19 is the opposite of this angle, and the side 35 is adjacent to the angle.
We use the tangent ratio to tie the two sides together
[tex]\tan(\text{angle}) = \frac{\text{opposite}}{\text{adjacent}}\\\\\tan(x) = \frac{19}{35}\\\\x = \tan^{-1}\left(\frac{19}{35}\right)\\\\x \approx 28.4956386\\\\x \approx 28\\\\[/tex]
Note: The notation [tex]\tan^{-1}[/tex] refers to the inverse tangent, or arctangent.
I need help ASAP!!!Please explain your answer
Answer:
Step-by-step explanation:
There are 2 possibilities. Either you need to know the angles connect to the common side (that would give you ASA) or you need to know GF = UT. The latter would give you SAS
Value of the boat after 3 years?
after each year it's 83% of it's value from last year (100%-17%=83%)
the function in 19000 * (0.83) ^x
3 will be filled in for x
19000 * (0.83) ^3= 10863.953
$10863.95
Answer:
$10,863.95
Step-by-step explanation:
y = 19,000[tex](.83)^{t}[/tex]
y = 19,000[tex](.83)^{3}[/tex]
y =$10,863.95
PLEASE HELP :( ASAP
Find the area.
A. 272 cm²
B. 175 cm²
C. 189 cm²
D. 195 cm²
Answer:
A. 272 cm^2
Step-by-step explanation:
The area of the rectangle is 17cm * 7cm = 119 cm^2
The area of the right triangle is (25-7) * 17cm * 1/2 = 153cm^2
Answer: 119+153 = 272 cm^2
The area of triangle PQR is 231 cm2 , and PQ = 21 cm. Find the altitude SR. Help me solve this
Answer:
SR = 22 cm
Step-by-step explanation:
area = bh/2
(21 cm)(h)/2 = 231 cm^2
21h = 462 cm
h = 22 cm
SR = 22 cm
Which of the following functions is graphed below?
15
10
5
-8 -6 -4 -2 0
2
4 6 8
ch
[x® -3,xs 2
A. y =
1x2 +6, x> 2
O B. y -
[x2 -3.x > 2
1x2 +6, 52
O c. y-{X-3,x<2
1x2 +6, xs 2
x < 2
O D. y =
(x² – 3, x<2
(x2 +6, x2 2
___________________A
The function that represents the inequality of the given graph is;
Option A
Graph Inequalities
From the given graph, the curve with the shaded dot shows less than or equal to because the dot indicates that the maximum input value of x is at that point.
Secondly, the curve without a shaded dot shows that the input function of x is only greater than 3.
Looking at the options, option A is right and we will prove it thus;
for y = x³ - 3
At x = 2, we see that;
y = 2³ - 3
y = 5
This corresponds with the given equation
For the second curve, for y = x² + 6;
At x = 2, we have;
y = 2² + 6
y = 4 + 6
y = 10
This corresponds with what is given and is thus correct.
Thus, option A is the correct answer
Read more about graphed inequalities at; https://brainly.com/question/11234618
Find the missing value.
Hint: Use the number line to find the missing value.
4-
-2
开
出 Hy
15
-10
-5
-15
0
5
10
Answer:
6
I hope this helpedWhich equation matches the graph shown?
[tex]we conclude that option B:[/tex]
[tex]y + 5 = -\frac{1}{2}*(x - 3)^2[/tex]
[tex]Is the graphed function.[/tex]
Which equation matches the graph shown?On the graph we can see a parabola that opens downwards, so it has a negative leading coefficient.
We also can see that the vertex of the parabola is on the point (3, -5)
Then the equation of the parabola is something like:
y + 5 = a*(x - 3)^2
Where a is a negative real number.
The only option of this form is option B, so we conclude that option B:
[tex]y + 5 = -\frac{1}{2}*(x - 3)^2[/tex]
Is the graphed function.
If you want to learn more about parabolas:
https://brainly.com/question/4061870
#SPJ1
Geometry, please answer question ASAP
Answer:
D
Step-by-step explanation:
The median goes from the vertex to the midpoint of the opposite side, so
LN = NM , that is
3x - 7 = 5 ( add 7 to both sides )
3x = 12 ( divide both sides by 3 )
x = 4
Then
KL = 2x + 3 = 2(4) + 3 = 8 + 3 = 11 → D
PLEASE ELP ME ITS URGENT!!! 25 POINTS!!!!!
Write 2.4 × 1012 in standard notation.
Answer:
2,400,000,000,000
Step-by-step explanation:
2.4 x 10^12 means that the decimal point is moved 12 places to the right (hence the power of 12)
So by moving the decimal point 12 times you get this: 2,400,000,000,000
The reason why there are only 11 zeroes is because the 4 was a decimal place to the right of 2, thus losing a zero.
what is the lowest common denominator of 4 7 5 2 and 1
Answer:
140
Step-by-step explanation:
Lowest common denominator 4 , 7 ,5 , 2 and 1
= 4 * 7 * 5
= 140
Answer:
1
Step-by-step explanation:
Since usually common denominator is usually used with fractions (in this case), we can find out it's one because of how no numbers (except for 2 and 4) go into each other without a remainder except for one, so one would be the correct answer
Find the ordered pair $(s,t)$ that satisfies the system
\begin{align*}
\dfrac{s}{2} + 5t &= 3,\\
3t - 6s &= 9.
\end{align*}
Answer:
[tex]\left(\dfrac{8}{7} , \ \dfrac{17}{35} \right)[/tex]
Step-by-step explanation:
The given system of equations is presented as follows;
[tex]\dfrac{s}{2} + 5 \cdot t = 3[/tex]
3·t - 6·s = 9
Making t the subject of both equations, gives;
In the first equation; t = (3 - s/2)/5
In the second equation; t = (9 + 6·s)/3
Equating both values of t to find the the values that satisfies both equations, gives;
(3 - s/2)/5 = (9 + 6·s)/3
3 × (3 - s/2) = 5 × (9 + 6·s)
9 - (3/2)·s = 45 + 30·s
45 - 9 = (30 + (3/2))·s
36 = (63/2)·s
s = 36/(63/2) = 8/7
t = (3 - s/2)/5
∴ t = (3 - (8/7)/2)/5 = 17/35
Therefore, the ordered pair is (8/7, 17/35)
Please help me find the area of the figure!!
Answer: 199 square yards
Step-by-step explanation:
If you break it down into 3 rectangles it’ll be easier to find the answer. Multiply it by H x W. First you do the 6 x 10. And then afterwards add the extra 5 to the 6 and it’ll make the
H = 11, and the W is 4. And then add the last 3 to H and it’ll make it 19 and the last W is 5
6 x 10 = 60
11 x 4 = 44
19 x 5 = 95
Total of 199
Hope this helps :)
question 22 , the triangle one
9514 1404 393
Answer:
9.1 cm
Step-by-step explanation:
Corresponding sides of similar triangles are proportional.
PQ/PR = AB/AC
PQ/21.7 = 5.2/12.4 . . . . . . . . . . . . . . fill in the given values
PQ = 21.7(5.2/12.4) . . . . . multiply by 21.7
PQ = 9.1 . . . cm
PLZZZZ HELPPPPPP!!!!!!!!!!!
Answer:
5/8 boxes
Step-by-step explanation:
1/3 ⋅ 1 7/8 = ?
1/3 ⋅ 15/8 = 15/24
15/24 = 5/8
5/8 boxes
A hot air balloon is released into the air. During its straight ascent, the angle of elevation was 15° and, 3 minutes later, the angle of elevation increased 20°. How fast is the balloon traveling, in km/h, if the angle measurements were taken 300m away from the launch site?
Answer:
The speed of balloon is 0.16 m/s.
Step-by-step explanation:
BC = 300 m
AD = x
AB = y
time, t = 3 min = 3 x 60 = 180 s
By the triangle, ADC,
[tex]tan 15 = \frac{AD}{BC}\\\\0.27 \times 300 = x \\\\x = 80.4 m[/tex]
By the triangle, BDC
[tex]tan 20 = \frac{BD}{BC}\\\\0.36 \times 300 = x + y \\\\x + y = 109.2 m[/tex]
So, y = 109.2 - 80.4 = 28.8 m
Speed of balloon = 28.8/180 = 0.16 m/s
The tens digits of a certain two-digit number is 1/3 of the units digit. When the digits are reversed, the new number exceed twice the original number by 2 more than the sum of the digits. Find the original number.
Answer:
The orginal number is 26.
Step-by-step explanation:
So the units digit can be 3 6 or 9
The tens digit can be 1 2 or 3
So the original number can be 13
31 = 2*13+ (1+3) + 2
31 =? 26 + 4 + 2
This doesn't work. The right side is 32
26
62 = 2*26 + 8 + 2
62 = 52 + 8 + 2
This is your answer.
3 and 9 won't work because 39 is odd and so is 93. The result has to be even.
Write the quadratic expressions in the numerator and the
denominator in factored form
4x^2-14x+6/
X^3-7x^2+12x
I have to give 2 Ans form my question so sorry
Need help ASAP!!!!Make sure you can explain your answer
Answer:
see below
Step-by-step explanation:
point A(x,y) becomes A'(-x,-y).
So point E (-3,-5) becomes E'( 3,5)
F (-1,-1) becomes F'(1,1)
and G (0,-5) becomes G'( 0,5)
4. Is 1,500,000 grams in 3 liters the same as 5 kilograms in 1 centiliter?
O No, because "grams per liter" measures volume, and "kilograms per centiliter" measures length.
No, because "grams per liter" measures concentration, and "kilograms per centiliter" measures area.
O Yes, because 1 kilogram = 1000 grams, and 1 liter = 100 centiliters.
Yes, because 1 gram per liter is the same as 1 kilogram per centiliter.
Answer:
O Yes, because 1 kilogram = 1000 grams, and 1 liter = 100 centiliters.
Yes, because 1 gram per liter is the same as 1 kilogram per centiliter.
Step-by-step explanation:
Independent Practice
Find the first, fourth, and eighth terms of the sequence.
an=0.5 · 3n−1a subscript n baseline equals 0.5 times 3 superscript n minus 1 baseline
A.
0.667; 4.5; 364.5
B.
3; 0.375; 0.0234375
C.
0.5; 13.5; 1093.5
D.
0.5; 121.5; 280.5
Answer:
C.
0.5; 13.5; 1093.5
Step-by-step explanation:
Can you help me on 19?
Answer:
7+k=0
7-0=k
k=7
Step-by-step explanation:
7+k=0
7-0=k
k=0
Mr. Ellington has a total of 32 students in his class , The ratio of girls to boys is 3:5, how many girls are in Mr . Ellington's class ?
Add the ratio: 3 + 5 = 8
Divide total students by that:
32/8 = 4
The ratio for girls is 3, multiply the 4 by 3:
4 x 3 = 12
There are 12 girls
Answer:
12
Step-by-step explanation:
If the ratio of girls to boys is 3:5, that means that for every 8 total students, 3 would be girls and 5 would be boys. Therefore 3/8 of the students are girls and 5/8 are boys. If 3/8 are girls, then:
[tex]\frac{3}{8}[/tex] of 32
= [tex]\frac{3}{8} * 32[/tex]
[tex]=\frac{3 * 32}{8} \\= \frac{96}{8} \\= 12[/tex]
There are 12 girls.
Help anyone can help me do the question,I will mark brainlest.
Answer:
a) 30
b)600pi
Step-by-step explanation:
For the first questions, since the arc is 240°, the area of the sector and circumference will be 240/360 or 2/3 of the total of the circles'. Therefore 125.6 x 3/2 is the circumference, which is 188.4. When we divide this by 6.28, we get 30
Now, since the area is pi r^2 where we know that r=30, we get 900pi as the area of the whole thing, however since the sector is 2/3 of the whole circle, 2/3 x 900pi = 600pi
Write an
equation
in slope y-intercept form B(-4,-3),m =Undefined
Answer:
x=-3
Step-by-step explanation:
maths question please help !! thank u :)
Answer:
1350m
Step-by-step explanation:
Let the distance ran by Denise, Farah and Elaine be D, F and E meters respectively.
From the given information,
D= ⅔(E +F) -----(1)
E= ½(D +F) -----(2)
Let's get rid of the fraction so the equations are much easier to work with.
From (1):
3D= 2(E +F) (Multiply both sides by 3)
3D= 2E +2F -----(3) (Expand)
From (2):
2E= D +F -----(4)
Substitute (4) into (3):
3D= D +F +2F
3D -D= 3F
2D= 3F
Given that Farah ran 360m, F= 360.
2D= 3(360)
2D= 1080
D= 1080 ÷2
D= 540
2E= D +F
2E= 540 +360
2E= 900
E= 900 ÷2
E= 450
Total distance the 3 girls ran
= D +F +E
= 540 +360 +450
= 1350m
Alternatively, you could start by substituting F= 360 to equations (1) and (2).
The 12th term of the arithmetic sequence is 10.5. The 18th term of this sequence is 13.5. Find the common difference and the first term
Answer:
common difference is 0.5
first term is 5
Step-by-step explanation:
use the formula for the nth term of an ap Tn=a+(n-1)d
T12=10.5
T18=13.5
therefore come up with two equations
T12=a+(12-1)d
10.5=a+11d(1st equation)
T18=a+(18-1)d
13.5=a+17d(2nd equation)
then solve both as a simultaneous equation
a+11d=10.5
a+17d=13.5
-6d/-6=-3/-6
d=0.5
use one of the equations to find the first term
a+11(0.5)=10.5
a+5.5=10.5
a=10.5-5.5
a=5
I hope this helps
please mark as brainliest
PLEASE HELP WILL MARK BRAINLIEST!!!! You work for a consumer advocate agency and want to find the mean repair
cost of a washing machine. As part of your study, you randomly select 40
repair costs and find the mean to be $120.00. The sample standard deviation
is $17.50. The 99% confidence interval for the population mean repair cost is? A.(112.86, 127.14) B.(114.58, 125.42) C. (115.43, 124.57) D. (111.57, 128.43)
Answer:
The correct answer is - A.(112.86, 127.14)
Step-by-step explanation:
Given:
mean = $120
sd = $17.50
n = 40
Solution:
Confidence interval for a populationcan be express as mean +/- margin of error (E)
degree of freedom = n-1 = 40-1 = 39
confidence level (C) = 99% = 0.01
significance level = 1 - C = 1 - 0.01 = 0.99 = 99%
by margin of error E = t×sd/√n = 2.58*17.50/√40
= 2.58*2.76
= 7.138 or 7.14
then the lower limit of mean = mean - E = 120 - 7.14 = $112.86
and, the upper limit of population mean = mean + E = 120 + 7.14 = $127.14
