Question

Use the formula for the total surface area of a cone to solve for the slant height, l.

Answer 1

Answer B)
`I=(S-\pi*r^2)/(\pi*r)`

Explanation:

From the given formula, we solve for the unknown by first keeping on one side of the equation the term that contains the unknown and then by dividing both sides by the variables and constants that accompany the unknown "I" in order to isolate it:

`S=\pi *r*I+\pi *r^2\\S-\pi*r^2=\pi*r*I\\(S-\pi*r^2)/(\pi*r) =I\\I=(S-\pi*r^2)/(\pi*r)`

Which coincides with answer B)