Answer
-6, 7
Work Step by Step
Since the coefficient of the squared term is one, we know that the expression must factor to:
$$ (x\pm a)(x\pm b)$$
Here, we see that a and b must multiply to get $-42$ and add to get $-1$. Thus, we find that the solution is:
$$(x-7)(x+6)$$
Setting these equal to zero, the solution is:
$$x=-6,7$$