Remark
This is a quadratic. You can factor it, which is the easiest way to do it. A graph (which I will enclose) will confirm the answer.
Solve
a^2 + 8a + 7 = 0
(a + 7)(a + 1) = 0
This means there are 2 points where the graph hits the x axis and y = 0
x + 7 = 0
x = -7
The intercept point is (-7,0)
x+ 1 = 0
x = - 1
The intercept point is (-1,0)
Answer
The two points that solve this quadratic are
(-1,0) and (-7,0) <<<<<< Answer.
The graph below shows the same thing. Notice that the graph cuts the axis at the two points designated as the answer. If there are choices with this question please list them.