A sector of a circle has area of 70pi cm^2 and a central angle of 5pi/7. What is the arclength of the sector? Answer as an exact value.

soy nueva

Step-by-step explanation:

:3

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.