Answer:
BC = 29.4
Step-by-step explanation:
30² = 20² + BC² -2•20•BC•cos(108)
900 = 400 +BC² -12.4•BC
900 -400 = BC² -12.4•BC
BC² -12.4•BC -500 = 0
Solve the equation using Bhaskara and you'll find two possible values for BC, which are:
BC = -17 and BC = 29.4
A negative number doesn't make sense because it is a side of a triangle, so we choose BC = 29.4
HELP PLS!! ILL GIVE POINTS !! :(( m
Find the product of the complex numbers. Express your answer in
trigonometric form.
Z1 =5(cos15° + i sin 15°)
Z2=3(cos70° + i sin 70°)
A. 8(cos85° + isin85°)
B. 2 (cos(-55°) + i sin(-55°))
C. 2 (cos305° + i sin 305°)
D. 15(cos85° + i sin85°)
Answer: Choice D
15(cos85° + i sin85°)
===========================================================
Explanation:
Let's say we had these two general complex numbers, which are in polar form.
[tex]z_1 = r_1*\left(\cos(\theta_1)+i*\sin(\theta_1)\right)\\\\z_2 = r_2*\left(\cos(\theta_2)+i*\sin(\theta_2)\right)\\\\[/tex]
We can abbreviate them into the shorthand form
[tex]z_1 = r_1*\text{cis}(\theta_1)\\\\z_2 = r_2*\text{cis}(\theta_2)\\\\[/tex]
The notation "cis" stands for "cosine i sine".
Now that we have those complex numbers set up, multiplying them is as simple as saying this:
[tex]z_1*z_2 = (r_1*r_2)*\text{cis}(\theta_1+\theta_2)[/tex]
We do two basic things:
Multiply the r values out frontAdd the theta values inside the the cis function---------------------------------------
With all that in mind, let's tackle the problem your teacher gave you.
The given complex numbers
[tex]z_1 = 5*\left(\cos(15^{\circ})+i*\sin(15^{\circ})\right)\\\\z_2 = 3*\left(\cos(70^{\circ})+i*\sin(70^{\circ})\right)\\\\[/tex]
abbreviate into
[tex]z_1 = 5*\text{cis}(15^{\circ})\\\\z_2 = 3*\text{cis}(70^{\circ})\\\\[/tex]
then those multiply to
[tex]z_1*z_2 = (r_1*r_2)*\text{cis}(\theta_1+\theta_2)\\\\z_1*z_2 = (5*3)*\text{cis}(15+70)\\\\z_1*z_2 = 15\text{cis}(85^{\circ})\\\\z_1*z_2 = 15\left(\cos(85^{\circ})+i\sin(85^{\circ})\right)\\\\[/tex]
which is why choice D is the final answer.
Two friends go to a Mexican restaurant for lunch. One friend orders 1 soft taco and
3 burritos and his bill was $8.75. The other friend's bill was $10.00 and he ordered 4
soft tacos and 2 burritos. What is the cost of a taco and what is the cost of a
burrito?
The cost of a taco is:
The cost of a burrito is:
Answer:
cost of a taco: $1.25
cost of a burrito: $2.50
Step-by-step explanation:
Let the cost of a taco be $t and the cost of a burrito be $b.
t +3b= 8.75 -----(1)
4t +2b= 10
Divide both sides by 2:
2t +b= 5
Making b the subject of formula:
b= 5 -2t -----(2)
Substitute (2) into (1):
t +3(5 -2t)= 8.75
Expand:
t +3(5) +3(-2t)= 8.75
t +15 -6t= 8.75
t -6t= 8.75 -15
-5t= -6.25
t= -6.25 ÷(-5)
t= 1.25
Substitute t= 1.25 into (2):
b= 5 -2(1.25)
b= 5 -2.5
b= 2.50
Thus, the cost of a taco is $1.25 and the cost of a burrito is $2.50.
HELP PLEASE BRAIN FOR CORRRECT
Answer:
1/6
Step-by-step explanation:
you divide y by x
y ÷ x
each column when you you divide y by x the answer is 1/6
Alberto quiere envasar 32 toneladas de arroz en sacos de 15 kilogramos cada uno, ¿Cuántos sacos necesitarán?
PLZZZ HELPPP, IF NOT 100% SURE PLZ DONT ANSWER…BRAINLIEST TO FIRST AND CORRECT ANSWER, THX TO SECOND AND CORRECT ANSWER
=============================================================
Explanation:
1/2 = 4/8 after multiplying top and bottom by 8
So the mixed number 7 1/2 is the same as 7 4/8
We can convert to an improper fraction like so
7 4/8
7 + 4/8
7*(8/8) + 4/8
56/8 + 4/8
(56+4)/8
60/8
Notice how dividing 60 over 8 leads to 7 remainder 4. Think of it like having 60 cookies and you want to share them amongst 8 friends. Each friend gets 7 whole cookies (7*8 = 56 taken so far) and then we have 60-56 = 4 left over as the remainder.
Through similar steps, you should find that the mixed number 1 7/8 converts to the improper fraction 15/8.
-----------------------------
To rephrase the problem with improper fractions would be to say:
"The electrician needs to buy 60/8 feet of wire. There are 15/8 feet of wire in each spool. How many spools should the electrician buy?"
Let x be the answer to that question.
We multiply the number of spools (x) by the amount of feet of wire per spool (15/8) to get the expression (15/8)x
Set this equal to the target 60/8 and solve for x
(15/8)x = 60/8
15x = 60 .... multiply both sides by 8 to clear out the fractions
x = 60/15
x = 4
The electrician needs to buy exactly 4 spools
-----------------------------
A different approach could have us convert each mixed number into decimal form
7 1/2 = 7 + 1/2 = 7 + 0.5 = 7.5
1 7/8 = 1 + 7/8 = 1 + 0.875 = 1.875
So the electrician needs to buy 7.5 ft total and each spool has 1.875 ft of wire.
Using the same idea as before, we would then have,
1.875x = 7.5
x = (7.5)/(1.875)
x = 4
13 Water is pulled up from a well in a bucket on a rope. The rope winds on a cylindrical drum 15 cm in diameter. It takes 28 turns of the drum to pull the bucket up from the bottom of the well. How deep is the well? (Use the value 2 for m.)
PLS HELP ME ON THIS QUESTION I WILL MARK YOU AS BRAINLIEST IF YOU KNOW THE ANSWER!!
The median of the lower half of the data set is the _____________.
A. Third quartile
B. First quartile
C. Fourth quartile
D. Second quartile
Answer:
B. First quartile
Step-by-step explanation:
The first quartile is the first 25% of a line graph, and the median of the lower half of a data set would be the median of the median, which means it would split the graph at 25%
In a random sample of 190 people, 151 said that they watched educational television. Find the 90% confidence interval of the true proportion of people who watched educational television. Round intermediate answers to at least five decimal places. Round your final answers to at least three decimal places.
Answer:
(0.7465 , 0.8429 )
Step-by-step explanation:
Confidence Level - "P" values
90% 1.645
Confidence Interval - "P" values
(0.7465 , 0.8429 )
Translate to an equation, then solve.
Nineteen less than six times a number is equal to 11 more than four times the number?
What is the number?
Answer:
15Step-by-step explanation:
Let the number is x, then we have:
6x - 19 = 4x + 116x - 4x = 11 + 192x = 30x = 15Find the value of x-8 when x=16.
Answer:
8
Step-by-step explanation:
x=16
x(16)-8=8
please help, i will give brainliest!
Answer:
yes please, ask the question
Elias made a polyhedron with 9 edges and 5 faces. Which solid could he have made?
The polyhedron that Elias could have made is a TRIANGULAR BASED PRISM.
Triangular based prism are as described below:
A triangular-based prism is known to consists of 9 edges and 5 faces as shown in the diagram below.
It is a three-sided prism and also a polyhedron made of a triangular base, a translated copy, and 3 faces joining corresponding sidesThe edges are made up of lines and these lines are the ones that intersect to form facesLearn more here: https://brainly.com/question/16682058
Answer: c
Step-by-step explanation:
Which shows two triangles that are congruent by ASA?
Answer:
A and D
Step-by-step explanation:
The two triangles that are congruent by ASA is discussed below.
What is Congruency?Two figures are said to be "congruent" if they can be positioned perfectly over one another. Both of the bread slices are the same size and shape when stacked one on top of the other. "Congruent" refers to things that are precisely the same size and shape.
Angle-Side-Angle refers to the ASA Congruence rule.
According to this rule, two triangles are said to be congruent if any two of their respective angles and the side that is included between them are equal to the corresponding angles and the included side of the other triangle.
For example, there are ABC and DEF in which ∠ B = ∠ E, ∠ C = ∠ F, and BC = EF
Then, the triangle that Δ ABC ≅ Δ DEF by ASA congruence rule.
Learn more about Congruency here:
https://brainly.com/question/7888063
#SPJ5
Answer ASAP Please!
cos(13°) correct to four decimal places is:
A:0.2311
B:0.2312
C:0.9734
D:0.9735
E:0.9744
Answer:
E:0.9744
Step-by-step explanation:
Answer: E) 0.9744
Explanation:
This is something you'll need a calculator for. As far as I know, there isn't a clean formula that will allow you to compute this by hand, and get something like sqrt(3)/2. There is a way to find the decimal value by hand, but it will require knowledge of Taylor polynomials and it will take a very long while to compute the value. So again, it's better to use a calculator. When using a calculator, make sure it's in degree mode. You can check by computing cos(60) and you should get 0.5
An athlete throws her javelin 9.5 yards. She throws it this distance 2 times. How far she throw her javelin in total
Answer: 19 yards
Step-by-step explanation: 9.5x2=19
NEED some HElp please
Explain why the amount of money in the account at the end of the first year is given by the formula with n as the exponent:
P = P∨0 (1 + r/n)^n
Answer:
Is this answer correct.Does the anwer help you
(4,-5) with slope of 2
that's a point slope form so
y +5 = 2(x -4)
3
Select the correct answer.
The angle of depression between the top of a 100-foot cliff and a ship approaching the shore is 37°.
cliff top
37°
100
feet
37°
ship
d
What is the approximate distance, d, between the bottom of the cliff and the ship?
ОА
166.2 feet
OB. 60.2 feet
ОС.
75.4 feet
OD.
132.7 feet
Reset
Next
Answer:
132.7 feet.
Step-by-step explanation:
tan 37 = height of cliff / distance of the ship
= 100/d
d = 100/tan37
= 132.7 feet.
The lengths of the diameters of two concentric circles are 6 and 8. What is the distance between the circles?
Answer: 1 unit
Explanation:
The diameters are 6 and 8, which cut in half to 3 and 4 respectively.
The difference in these radii values is 4-3 = 1.
This is the distance from one circle's edge to the other circle's edge, such that we're on the same line that goes through the center of the circles. This is the gap width or ring width so to speak.
Find f(-3) if f(x) = x2 .
Type a numerical answer in the space provided. Do not type spaces in your answer.
Answer:
f(-3) = 9
General Formulas and Concepts:
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightAlgebra I
Functions
Function NotationStep-by-step explanation:
Step 1: Define
Identify
f(x) = x²
Step 2: Evaluate
Substitute in x [Function f(x)]: f(-3) = (-3)²Exponents: f(-3) = 9x.(9x-1).(x+2)-x(3x-1).(3x+1)
Answer:
Sorry if i'm wrong.
=6x² + 16x - 2
write x²-y² in factorize form.
write (p+p) ²in expanded form.
Answer:
(x-y)^2
p^2+p^2
Step-by-step explanation:
^2 means square
Answer:
see explanation
Step-by-step explanation:
x² - y² ← is a difference of squares and factors in general as
a² - b² = (a - b)(a + b) , then
x² - y²
= (x - y)(x + y)
------------------------------
(p + p)²
= (2p)²
= 2p × 2p
= 4p²
The football team loses 5 yards on first down.
a. Write an integer to represent this situation.
Answer:
-5
Step-by-step explanation:
since it is a lose, it is represented by a negative sign.
Sandra is 5 years old. When she asked her father about his age, he gave her this answer. "When you are my age, I will be 67." How old is her dad?
Step-by-step explanation:
Her father is 34 years old
Joylin is writing an equation to model the proportional relationship between y, the total cost in dollars of downloading videos from a website, and x, the number of videos downloaded. She knows that the total cost to download 3 videos was $12. Her work to find the equation is shown below.
Joylin’s Work
Step 1
k = StartFraction 3 over 12 EndFraction = 0.25
Step 2
y = 0.25 x
Where did Joylin make her first error?
Answer:
Step-by-step explanation:
Jocelyn was attempting to find out how much she will be charged per download. She has the fraction upside down. To find the amount of money per download, the fraction should be $12/3downloads to get $4/1download. That is the slope of the equation, the rate of change or, for us, the fact that your cost will go up $4 for every single video you download. The equation would then be
y = 4x
The way she has it, we are paying only a quarter for a download. If that be the case, for 3 downloads we would only be paying .75, but it says we pay $12, so we know something is wrong right there.
Answer:
The answer is A
Step-by-step explanation:
Write the function for the graph.
Answer:
B)
Step-by-step explanation:
exponential function given by:
[tex] \displaystyle f(x )= a \cdot{b}^{x} [/tex]
where:
a is the y-interceptb can be any numbersince the function crosses y-axis at (0,4) point
[tex]a = 4[/tex]to find a we can consider (1,8) point it tells us when x is 1 then y is 8 thus:
[tex] \displaystyle 8= 4 \cdot{b}^{1} [/tex]
[tex] \displaystyle 8= 4 \cdot{b}^{} [/tex]
divide both sides by 4:
[tex] \displaystyle \boxed{b = 2}[/tex]
altogether substitute:
[tex] \displaystyle f(x)= 4 \cdot{2}^{x} [/tex]
hence our answer is B)
What is the correct answer to this multiple choice question? Please help!
Answer:
[tex]\sqrt[3]{4}[/tex]
Step-by-step explanation:
To solve this we need to take the square root of both sides with a certain degree.
[tex]4^6 = a^{18}[/tex]
We can take the root of both sides with a degree of 18.
[tex]\sqrt[18]{4^6} = \sqrt[18]{a^{18}} \\(4^6)^{\frac{1}{18} } = a\\a = 4^{\frac{6}{18} } = 4^{\frac{1}{3} } = \sqrt[3]{4}[/tex]
It's helpful to understand that when a number has its square root taken with some degree n. The square root can be represented as just the value raised to the (1/n) power.
It's also helpful to understand that when you raise something to the power of another power, you can simply multiply the powers together. For instance (2^3)^5 = 2^15
PLEASE HELP WILL GIVE BRAINLIEST!!!!
Answer:
wqhg
Step-by-step explanation:
its situated in u.s, in quahog , rhode island
What is the expected value?
Answer:
2.1
Step-by-step explanation:
The expected value of a probability is given by the formula:
E(x) = Σxp(x)
Therefore from the table showing the winnings of a game, the expected value of the probability distribution is:
E(x) = Σxp(x) = (0 * 0.5) + (2 * 0.2) + (4 * 0.15) + (6 * 0.1) + (10 * 0.05)
E(x) = 0 + 0.4 + 0.6 + 0.6 + 0.5 = 2.1
Hence we can conclude that the expected value of the winnings of the game is 2.1.
Please help: 6m - m = 5/6(6m - 10)
Will mark brainliest!!
Answer:
No solution.
Step-by-step explanation:
[tex]6m-m=\frac{5}{6}(6m-10)\\5m=5m-\frac{25}{3}\\0\neq -\frac{25}{3}[/tex]
Therefore, there is no solution.