S=πrl+πr2 solve for l.

Step-by-step explanation:

s = πrl + πr²

First move πr² to the left side of the equation

We have

πrl = s - πr²

Divide both sides by πr to make l stand alone

That's

We have the final answer as

Hope this helps you

check the picture below.

well, the angle at the vertex d is clearly not a right-angle, let's check for the one at the vertex f which does look like,   however if it's indeed, that means ef is perpendicular to df, in which case their slopes will be negative reciprocal of each other.

so the negative reciprocal of the slope of ef is 1, however the slope of df is not 1, is 1/2, so nope, they're not perpendicular lines.

180

step-by-step explanation: