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stupidinmath
how to factor 64x^2=81
(8x-9)(8x+9). but, what are the steps?
(4)^2x^2 - 9^2 (4x)^2 - (9)^2 x^2 - y^2 = (x - y)(x + y ) hence the answer ;)
64x^2=81 so sqrt everything -> 8x = plus/minus 9 -> (8x +9)(8x -9)