Final answer:
The value of a in the factored form of the quadratic function with x-intercepts at -1 and -7, which also passes through the point (-2, -20), is 4.
Step-by-step explanation:
The student is asking to find the value of a in the factored form of a quadratic function with x-intercepts at -1 and -7 that also passes through the point (-2,-20). The factored form of this function would be a(x + 1)(x + 7). Since we know the function passes through the point (-2,-20), we can substitute these values into the equation to determine the value of a.
Plugging in the point, we get:
-20 = a(-2 + 1)(-2 + 7)
-20 = a(-1)(5)
-20 = -5a
To solve for a, divide both sides by -5:
a = -20 / -5
a = 4
Hence, the value of a is 4, which corresponds to option c).