factor completely
2x^2 + 11x - 13
x^2 + 6x + 9
4x^2 + 20x + 25
9x^2 - 12x + 4
x^2 - 16
36x^2 - 4t^2
5x^3 - 10x
2x^2 + 11x - 13 = (2x - 1)(x + 13)
x^2 + 6x + 9 = (x + 3)(x + 3) = (x + 3)^2
4x^2 + 20x + 25 = (2x + 5)(2x + 5) = (2x + 5)^2
9x^2 - 12x + 4 = (3x - 2)(3x - 2) = (3x - 2)^2
x^2 - 16 = (x - 4)(x + 4)
36x^2 - t^2 = (6x - t)(6x + t)
5x^3 - 10x = 5x(x^2 - 2) = 5x(x - √2)(x + √2)