a ladder 10m long rests against a vertical wall if the foot of the ladder is 6m away from the wall and the ladder just reaches the top of the wall then how high is the wall

If (x + 8) is a factor of f(x), which of the following must be true? both x = –8 and x = 8 are roots of f(x). neither x = –8 nor x = 8 is a root of f(x). f(–8) = 0 f(8) = 0