Answer:
4x iss the GCF that was factored out.
Explanation:
Given the equation 4x²+8x, the greatest common factor will be the maximum factor of 4x² and 8x and that is 4x. Factoring out 4x from the given equation will result into the equation;
4x(x+2)
Note that the the resulting value in the bracket must have no other common factor after the GCF must have been factored out.
Therefore the expression that was factored out using GCF was 4x