Idon't understand this question. can someone explain to me in steps how to do this part a: the area of a square is (4a2 − 20a + 25) square units. determine the length of each side of the square by factoring the area expression completely. show your work. part b: the area of a rectangle is (9a2 − 16b2) square units. determine the dimensions of the rectangle by factoring the area expression completely. show your work.