Answer
$(x+7)(x+1)$
Work Step by Step
RECALL:
A trinomial of the form $x^2+bx+c$ (leading coefficient is 1) can be factored if there are factors of $c$ (say, $d$ and $e$) whose sum is equal to $b$.
The trinomial factors as $(x+d)(x+e)$
The given trinomial has a leading coefficient of 1 so the factoring technique mentioned above may be used.
Look for factors of $7$ whose sum is equal to 8.
Note that $7(1) = 7$ and $7+1=8$
This means that the given trinomial factors as $(x+7)(x+1)$.