Find the perimeter of a triangle that measures 2 ft by x ft by (8x+5) ft

There were 816 people at a concert when a band started to play. after each song, only half the people stayed to hear the next song. how many people were left at the concert after x songs? write a function to represent this scenario.

In the diagram, the ratio of ab to ae is (1/2) . what is the ratio of the length of to the length of ?

Estimate the area under the curve f(x) = 16 - x^2 from x = 0 to x = 3 by using three inscribed (under the curve) rectangles. answer to the nearest integer.