Answer: x = -2
Explanation:
Find 2 numbers whose product is the c-value of 4 and their sum is the b-value of 4.
x² + 4x + 4 = 0
∧
1 + 4 = 5
2 + 2 = 4 this works! so the factors are:
(x + 2)(x + 2) = 0
x + 2 = 0 and x + 2 = 0
x = -2 and x = -2 --> same answer so only need to list it once