Around which line would the following cross-section need to be revolved to create a sphere?

y=1

Step-by-step explanation:

we know that

When you will rotate a circle about its diameter, you will obtain a sphere

In this problem

The diameter of the circle pass through the y-axis and pass through the line y=1

so

If the cross section is revolved around the y-axis, then we will obtain a sphere

If the cross section is revolved around the y=1, then we will obtain a sphere

therefore

The answer is

y=1

center (1,3) with radius 6

step-by-step explanation:

we must complete the square to find the center and radius of the circle.

first make sure the x and y squared terms have 1 as their coefficients. we also make sure x and y terms together.

we now create space between the x and y terms with parenthesis.

we complete the square by taking the middle terms -2x and the -6y - divide each and square them.

we add the squares to both sides.

simplify.

and write the quadratics in factored form.

the center is (h,k) or (1,3). the radius is the square root of 36 which is 6.

answer: 8

step-by-step explanation: