You factored the difference of 2 cubes and you got 0 = (x – 7)(x^2 + 7x + 49). What are the solutions to this equation?

Question

A) {7, -7/2 ± (7/2)i sqrt(3)}
B) {7, -7/2 ± (7/2)i sqrt(7)}
c) {-7, 7/2 ± (7/2)i sqrt(3)}
D) There is only one solution: x = 7
E) {7, -7 ± 7i sqrt(3)}

Answer 1

D. x=7  By making the first (x-7) substituting x=7 would result in 0,  that 0 time the second equation would be the only way to make the out come = to 0.  Using -7 does not result in 0.