18x 2 x 4 0 July 8, 2019 16 32 64 128 X 2 18x 4 0 complete the square X 4 18x 2 81 0 X 4 18x 2 32 0 X 4 18x 2 80 0 X 4 13x 2 18x 5 0 X 4 7x 3 18x 2 0 18 - 4 x 2