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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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Darina [25.2K]

Answer:

7x-4 = -28

4y+8 = 4(y + 2)

Step-by-step explanation:

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2 years ago

write a polynomial expression that represents the area of a trapezoid with bases of 6x-5 and 4x+7, and a height of x+1.

tigry1 [53]

Answer:

A = 5x² + 6x + 1

Step-by-step explanation:

The area (A) of a trapezoid is calculated as

A = $\frac{1}{2}$ h (a + b)

where h is the height and a, b the parallel bases, thus

A = $\frac{1}{2}$ (x + 1)(6x - 5 + 4x + 7)

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4 years ago

What is 300+-50+-75+225

svetoff [14.1K]

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Working from left to right, 250 - 75 + 225

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3 years ago

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shepuryov [24]

Answer:

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Step-by-step explanation:

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3 years ago

PLZ HELP ASAP!!

Lilit [14]

The measure of first angle is 34 degrees and measure of second angle is 56 degrees

Solution:

Given that, the exterior sides of two adjacent angles make a right angle

Therefore, these adjacent angles forms 90 degrees

Let the second angle be "x"

The first angle has a measure that is six more than half the second

Therefore,

first angle = 6 + half of "x"

$\text{ first angle } = 6 + \frac{x}{2}$

Since these two angles forms 90 degrees,

first angle + second angle = 90

$x + 6 + \frac{x}{2} = 90\\\\\frac{2x + 12 + x}{2} = 90\\\\2x + 12+x = 180\\\\3x + 12 = 180\\\\3x = 180 - 12\\\\3x = 168\\\\x = 56$

Therefore, first angle is:

$\rightarrow 6 + \frac{56}{2} = 6 + 28 = 34$

Thus measure of first angle is 34 degrees and measure of second angle is 56 degrees

6 0

3 years ago