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ikadub [295]
3 years ago
14

Find the area of a circle whose diameter is 7cm​

Mathematics
2 answers:
dimulka [17.4K]3 years ago
7 0

Answer:

38.5 cm^2

Step-by-step explanation:

Diameter ( d ) = 7 cm

Radius ( r ) = 7 / 2 cm

Formula : -

Ar ( circle ) = π r^2

π r^2

= ( 22 / 7 ) x ( 7 / 2 )^2

= ( 22 / 7 ) x ( 49 / 4 )

= 38.5 cm^2

vodka [1.7K]3 years ago
4 0

Answer:

3.5pi

Step-by-step explanation:

just multiply together and you'll get your answer

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A container has 3 apple juice boxes, 4 grape juice boxes and 5 orange juice boxes. Alex picks one juice box, drinks it and then
Eduardwww [97]

Hey!

Grape over total: \frac{4}{12}

After he drinks 1, there will be 1 less. That means it will be over 11

Orange over total: \frac{5}{11}

Now multiply the fractions

\frac{4}{12} \times \frac{5}{11} = \frac{20}{132} \rightarrow \frac{10}{66} \rightarrow \frac{5}{33}

That means the probability is: \frac{5}{33}

Good luck and hope this helps! :)

4 0
3 years ago
A linear equation in two variables has infinitely many solution the set of all solutions to a linear equation in two variables f
Greeley [361]
<span>1, During a 1-hr television program, there were 22 commercials, Some commercials were 15 sec and some were 30 sec long. Find the number of 15- sec commercials and the number of 30 sec commercial if the total playing time for commercial was 9.5 minutes.

</span>a) <span>show how to formulate your system of equations for your problem,

Answer:
- state the variables: x number of 15 sec commercials, y number of 30 sec commercials
- translate the word statement into algebraic language

b) state the two equations:

- translate the word statement into algebraic equations:

</span><span>* there were 22 commercials => x + y = 22
* the total playing time for commercial was 9.5 minutes => 15x + 30y = 9.5*60 </span><span>

Answer:
Equation (1) x + y = 22
Equation (2) 15x + 30y =  570

c) state which method you will use to solve either addition or substitution

Answer:
adition: multiply the first equation times - 15 and add the two equations.

d) solve your system showing and explaining each step of the process

Answer:
- muliply eq (1) times - 15

-15x - 15y = - 330

- add that to the eq (2):

-15x + 15x - 15y + 30y = -330 + 570

- add like terms: 15y = 240

- divide both members by 15: 15y/15 = 240 / 15 => y = 16

- replace y = 16 in eq I(1) => x + 16 = 22 => x = 22 - 16 = 6

Solution: x = 6, y = 16

e) Be sure to check your solution!

x + y = 22
6 + 16 = 22
22 = 22 --> check

15x + 30y = 9.5*60
15(6) + 30(16) = 570
90 + 480 = 570
570 = 570 ---> check

f) Once a solution is found explain what this solution means in the context of the problem, write the answer to the word problem in words</span><span>

The solution means that d</span><span>uring a 1-hr television program, there were</span><span> 6 commercials of 15 sec and 16 commercials of 30 sec.

2, How many quarts of water should be mixed with a 30% vinegar solution to obtain 12 qt of a 25% vinegar solution. (Hint: water is 0% vinegar).</span>

a) variables:

- state the variables
x: number of quarters of water
y: number of quarters of vinegar

- translate the words into mathematical language

12 qt 25% vinegar solution

=> total number of quarts = 12 = x + y

balance in vinegar:

vinegar from water + vinegar from 30% vinegar solution = vinegar in the 25% vinegar solution

0 + 0.3y = 0.25 (x + y)

c) Equations

Eq (1) x + y = 12

Eq (2): 0.3y = 0.25x + 0.25y

=> 0.25x - 0.05y = 0

d) solve

- multiply eq (1) times 0.05 and add to eq (2)

0.05x + 0.05y = 0.6
0.25x - 0.05y = 0
------------------------
0.30x = 0.6

x = 0.6 / 0.3 = 2

x + y = 12 => y = 12 - y = 12 - 2 = 10

Solution: x = 2, y = 10

e) check:

x + y = 12
2 qt + 10qt = 12 qt
12 qt = 12 qt ---> check

vinegar:

10*0.3 = 12*0.25
3 = 3 -> check

f) Explanation of the solution

The solution means that you have to mix 2 qts of water with 10 qts of 30% vinegar solution to obtain 12 qt of 25% vinegar solution.

5 0
3 years ago
Write the simplest polynomial function with the zeros..?
zubka84 [21]
All u do is add up until u get ur answer
7 0
3 years ago
Find Sin A, Cos A, and Tan A given the following triangle.
Solnce55 [7]

Answer:

A

Step-by-step explanation:

sin A=(opposite side)/hypotenuse=a/c

cos A=(adjacent side)/hypotenuse=b/c

tan A=(opposite side)/(adjacent side)=a/b

8 0
3 years ago
Complete factorization f(x)=x^4-x^3-5x^2-x-6
Marianna [84]

The solution to the above  factorization problem is given as f′(x)=4x³−3x²−10x−1. See steps below.

<h3>What are the steps to the above answer?</h3>

Step 1 - Take the derivative of both sides

f′(x)=d/dx​​(x^4−x^3−5x^2−x−6)

Step 2 - Use differentiation rule d/dx​(f(x)±g(x))=d/dx​(f(x))±d/dx​(g(x))

f′(x)=d/dx​​(x4)−d/dx​​(x^3)−d/dx​​(5x^2)−d/dx​​(x)−d/dx​​(6)

f′(x)=4x^3−d/dx​​(x3)−d/dx​​(5x^2)−d/dx​​(x)−d/dx​​(6)

f′(x)=4x^3−3x2−d/dx​​(5x^2)−d/dx​​(x)−d/dx​​(6)

f′(x)=4x^3−3x^2−10x−d/dx​​(x)−d/dx​​(6)

f′(x)=4x^3−3x^2−10x−1−dxd​(6)

f′(x)=4x^3−3x^2−10x−1−0

Learn more about factorization:
brainly.com/question/25829061
#SPJ1

5 0
2 years ago
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