3 * 7 * x
No exponents necesary
21 isn't prime. The prime factorization of 42 is 2 x 3 x 7.
2x2+21x+49 = (2x+7)(x+7)
(2x+7)(x+7)
2x2 + 21x + 49 = 2x2 +14x +7x + 49 = 2x(x + 7) + 7(x + 7) = (2x + 7)(x + 7)
2x2 + 21x + 49= 2x2 + 14x + 7x + 49= 2x(x + 7) + 7(x + 7)= (x + 7)(2x + 7)
2x2 + 21x + 49 = (2x + 7)(x + 7)
9x-21x = -12
21x + 9 = 180 21x = 180 - 9 21x = 171 x = 171/21 x = 8.143
21x+452 = 32-84x 21x+84x = 32-452 105x = -420 x = -4
x2 - 21x = 72x2 - 21x - 72 = 0(x - 24) (x + 3) = 0x = 24x = -3
If: 9x = 21x-3 Then: x = 1/4 or 0.25
10x2y2 + 8xy2 - 210y2 = 2y2(5x2 + 4x - 105) = 2y2(5x2 + 25x - 21x - 105) = 2y2(x + 5)(5x - 21).