f(x) = g(x) will be the input or x value at which f and g have the same output or y value. Look in the table where two numbers repeat right next to each other.
−6 −4 1
−5 0 2
−4 4 4
−3 8 8
−2 12 16
−1 16 32
0 20 64
The solution to f(x)=g(x) is both x = -4 and x=-3.