Who is asking: Student


Hi, You need to look for patterns. Suppose that you have factored to get
and you are going to expand the right side to check your answer. When you expand the right side you get an x^{2} term, an x term and a constant term. The constant term is ab. Since the constant term on te left side is 12 you know that ab=12. Thus a and b are 1 and 12, 2 and 6, or 3 and 4. Expand them one at a time to see which one give 8x as the middle term.
Cheers, 

