0
Anonymous
x2 - 42x + 441 = (x - 21)2
Wiki User
Chat with our AI personalities
441 = 3 x 3 x 7 x 7
3 x 3 x 7 x 7 = 441
63 x 7 = 441
32 x 72 = 441
you have to make it into a one variable equation 21 * 21 = 7 * 7 * X 441 = 49 * X 441/49 = X 9 = X