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3 years ago

The sum of the areas of two circles is 80 pi

1 answer:

5 0

The area of a circle is A = πr^2. We let A1 And A2 the areas of the circles and r1 and r2 the radius of each, respectivley.

A1 + A2 = 80π
Substitute the formula for the area,
π(r1)^2 + π (r2)^2 = 80π

From the statement, we know that r2=2(r1).

π(r1)^2 + π (2 x r1)^2 = 80π
We can cancel π, we will have

5 x (r1)^2 = 80
Thus,

r1 = 4 and r2 = 8

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What is the lateral surface area on a square pyramid with base edges of 10 and the height of 12

8_murik_8 [283]

Answer:

joe mama

Step-by-step explanation:

7 0

3 years ago

An investor invested a total of $2,800 in two mutual funds. One fund earned 5% profit while the other earned 3% profit. If the i

Natasha_Volkova [10]

Answer:

The amount invested in the mutual fund that earned 5% was $1,000

The amount invested in the mutual fund that earned 3% was $1,800

Step-by-step explanation:

Let

x ----> the amount invested in the mutual fund that earned 5%

y ----> the amount invested in the mutual fund that earned 3%

we know that

$x+y=2,800$ ----> $y=2,800-x$ ----> equation A

$5\%=5/100=0.05$

$3\%=3/100=0.03$

$0.05x+0.03y=104$ ----> equation B

Solve the system by substitution

substitute equation A in equation B

$0.05x+0.03(2,800-x)=104$

Solve for x

$0.05x+84-0.03x=104$

$0.05x-0.03x=104-84$

$0.02x=20$

$x=\$1,000$

Find the value of y

$y=2,800-x$

$y=2,800-1,000=\$1,800$

therefore

The amount invested in the mutual fund that earned 5% was $1,000 and the amount invested in the mutual fund that earned 3% was $1,800

5 0

3 years ago

What is the value of the expression? 5^2 - 3^0

Vlad1618 [11]

5^2 = 25
3^0 = 1 (anything that is exponented by 0 is 1)

25 - 1 = 24

24 is your answer

hope this helps

5 0

3 years ago

Read 2 more answers

When you are given three side lengths for a triangle, how do you know which length to substitute for a, b, or c in the Pythagore

Romashka [77]

Answer:

When Sum of square of two Sides is equal to square of third side of triangle.

Step-by-step explanation:

Given:

Three side length of triangle are given we need find the which value to substitute for a, b, c in Pythagoras theorem.

First we will find the squares of all length, then we will check which two square of side are equal to square of third side as per Pythagoras theorem.

Hence the two side would according be a and b and third side will become c.

For example if length of triangle is given as 6 cm, 8 cm and 10 cm.

We will first take square of all

$6^2=36\\8^2=64\\10^2=100$