PLEASE HELP!!
joe wants to expand the size of his helicopter pad to have a radius of 11 ft. if his current helicopter pad has a radius of 8 ft, find the area that he must add to make this come true.

Question

PLEASE HELP!! 
joe wants to expand the size of his helicopter pad to have a radius of 11 ft. if his current helicopter pad has a radius of 8 ft, find the area that he must add to make this come true.

jdoe0001 · Answer

well. that's simple

his helicopter pad has a radius of 8
find that area

he wants to increase it to 11
find that area

subtract the area of radius 8 from the area of radius 11

recall that area of a circle = $\Large \pi r^2$    r = radius