The ratio of the volumes of two similar solid polyhedra is equal to the square of the ratio between their edges. true or false

If square root x = -7, then x= -49 true or false

What is the answer to this question? i'm a bit stumped. also how do i do it? 5(x - 4) = 2(x + 5)

An airplane travels at an unknown elevation before it descends 3 miles to an elevation of 15 miles. find the elevation of the plane before its descen.