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Can someone plz help me with this math problem.

Can someone plz help me with this math problem.-example-1

2 Answers

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radius is distance from center to the circle
diameter is from one isde to the other, it is also twice the radius

r=radius
d=diameter

circumfernce=pi times diameter or 2 times pi times radius
area=pi times radius^2

so


1.
circumference=2pir
radius=4.5
c=2pir
c=2pi4.5
c=9pi in

area=pir^2
arae=pi(4.5)^2
area=pi20.25
area=20.25pi in²




2.
diameter=12mi
circumfernce=pid
circumfernce=pi12
circumfnerce=12pi mi


area=pir^2
d/2=r
12/2=r=6
area=pi6^2
area=36pi mi²
User Lightbreeze
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5 votes
For question one, you would need to use the formula pi r ^2. So first you have 4.5, which is your radius(stands for r). Then you square it, which is 20.25. Then, you multiply 20.25 with pi. Then for circumference, you do 2 x pi x the radius which is 4.5. So for area, you get 63.62. Then for circumference you get 28.27.

For question 2, it is basically the same steps but instead you a diameter, not a radius. To get the radius, divide by 2, which the radius will be 6. Then from there, the radius is 6, and you solve the question.
User Metter
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