Which statement is true about the graphs of the two lines and? y = - 8x - 5/4 and y = 1/8x + 4/5

Y = - 8x - 5/4 ... slope here is - 8 or - 8/1

y = 1/8x + 4/5 ... slope here is 1/8

what u have here are negative reciprocal slopes ... negative reciprocal of a number can be found by flipping the number and changing the sign. So the negative reciprocal of - 8/1 is 1/8 (see how I flipped the number and changed the sign) ... and when u have negative reciprocal slopes, this means that ur lines are perpendicular.