37.9k views
4 votes
A sphere of radius 10 cm has the same surface area as a circle. what is the radius of the circle?

a) r=20

b) r=36

c) r=16

d) r=24

e) r= 48

User Ylebre
by
7.5k points

1 Answer

4 votes
The surface area of a sphere is given by the formula:

4 * pi * r^2

Where r is the radius of the sphere.

The surface area of a circle is given by the formula:

pi * r^2

Where r is the radius of the circle.

Since the sphere and the circle have the same surface area, we can set the formulas for the surface area of the sphere and the circle equal to each other and solve for r.

4 * pi * r^2 = pi * r^2

Simplifying, we get:

4 * r^2 = r^2

Dividing both sides by r^2, we get:

4 = 1

This equation does not have a valid solution, so all of the answer choices are incorrect. The correct answer is that it is not possible for a sphere and a circle to have the same surface area.

as I went over multiple times I recalculated this is what I came up with
User Sarena
by
7.6k points