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3 years ago

An architect increases the radius of a circle window by 20 percent. By what percent

Mathematics

2 answers:

Butoxors [25]3 years ago

7 0

Answer:

Step-by-step explanation:

For a circle of radius R, the area is written as:

A = pi*R^2

Where pi = 3.14

If we increase the radius by 20%, the new radius will be:

R´ = R + 0.20*R = 1.20*R

The new area will be:

A´ = pi*(1.20*R)^2 = (1.20)^2*pi*R^2

= 1.44*pi*R^2

And pi*R^2 = A, the original area, then_

A´ = 1.44*A = A + 0.44*A

This means that the percentage in which the area increased is:

0.44*100% = 44%

ale4655 [162]3 years ago

6 0

Answer: 44%

Step-by-step explanation:

For a circle of radius R, the area is written as:

A = pi*R^2

Where pi = 3.14

If we increase the radius by 20%, the new radius will be:

R´ = R + 0.20*R = 1.20*R

The new area will be:

A´ = pi*(1.20*R)^2 = (1.20)^2*pi*R^2

= 1.44*pi*R^2

And pi*R^2 = A, the original area, then_

A´ = 1.44*A = A + 0.44*A

This means that the percentage in which the area increased is:

0.44*100% = 44%

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Maurinko [17]

Let ABC be the triangle (with A as summit) and BC its base which is at the same time the diameter of the semi-circle. Let AH be the altitude of ABC.

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3 years ago

Part II: Find the angle O in radians, (2 points)

Savatey [412]

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3 years ago

Can someone help me if this is correct

malfutka [58]

Answer:

No, the correct answer is (c) 10 inches

Step-by-step explanation:

Triangles are always 1/2 the area of recatngles and to find the missing side of a rectangle, you just need to divide the area by known side.

Apply this knowledge to triangles:

First, I wanted to find the length of PR so that I can use the $A^{2} +B^{2} =C^{2}$ formula to find QR, so I just doubled the area of the triangle (24 -> 48) and divided it by QP (8) to get 6 for PR.