C. as t^2+t +t =t^4 + 9^2-3+3=9^2 = t^3 - 81 we are forced to -81 as we would be required to move t^3 first to the other side before -81 therefore if t is a perfect square of 4 and 9 is a perfect square too we can use. Since both terms are perfect squares, factor using the difference of squares formula,
