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3 years ago

The circumference of a circle is 3π in. What is the area of the circle? 1.5π in² 2.25π in² 6π in² 9π in²

Mathematics

2 answers:

Goryan [66]3 years ago

4 0

Answer:

B. $2.25\pi \text{ inches}^2$

Step-by-step explanation:

We have been given that the circumference of a circle is $3\pi$ inches. We are asked to find the area of the circle.

Since we know that the circumference of a circle is $2\pi r$ .

$\text{Circumference}=2\pi r$

Upon substituting the circumference as $3\pi\text{ inches}$ we will get,

$3\pi=2\pi r$

Let us divide both sides of our equation by $2\pi$ .

$\frac{3\pi\text{ inches}}{2\pi}=\frac{2\pi r}{2\pi}$

$\frac{3}{2}\text{ inches}=r$

$1.5\text{ inches}=r$

$\text{Area of circle}=\pi r^2$

Upon substituting r=1.5 in area of circle formula we will get,

$\text{Area of circle}=\pi*(1.5\text{ inches})^2$

$\text{Area of circle}=\pi*2.25\text{ inches}^2$

Therefore, the area of circle will be $2.25\pi \text{ inches}^2$ and option B is the correct choice.

dangina [55]3 years ago

3 0

C = 2πr
so
r = C/2π
r = 3π/2π
r = 3/2
r = 1.5

A = πr^2
A = π(1.5)^2
A = 2.25π

answer
2.25π in²

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Answer:

Part 1) Option B: 0 ≤ x ≤ 4

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Step-by-step explanation:

Part 1) we have

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V is the volume in gallons

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is equal to

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$10x^{2} -17x+3=0$

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$x=\frac{-(-17)(+/-)\sqrt{-17^{2}-4(10)(3)}} {2(10)}$

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$10(x-\frac{3}{2})(x-\frac{1}{5})=(2x-3)(5x-1)$

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$3=a(2-4)^2-1$

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$4a=4$

$a=1$

The quadratic equation is

$y=(x-4)^2-1$

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$(x-4)^2-1=0$

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$(x-4)^2=1$

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$x=4(+/-)1$

$x=4+1=5\\x=4-1=3$

therefore

The x-intercepts are the points (3,0) and (5,0)

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3 years ago

On a coordinate plane, a line goes through (negative 3, 2) and (0, 1). A point is at (3, 4).

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Answer:

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Points on given line: (-3, 2), (0, 1)

m1 = slope of given line; m = slope of perpendicular

Slope of given line = m1 = (y2 - y1)/(x2 - x1) = (2 - 1)/(-3 - 0) = 1/(-3) = -1/3

The slopes of perpendicular lines have a product of -1.

m1 * m = -1

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Point on perpendicular: (3, 4)

y - y1 = m(x - x1)

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3 years ago

The circumference of a circle is 3π in. What is the area of the circle? ​ 1.5π ​ in² ​ 2.25π ​ in² ​ 6π ​ in² ​ 9π ​ in²

The circumference of a circle is 3π in. What is the area of the circle? 1.5π in² 2.25π in² 6π in² 9π in²