Posted by ROCKY on .
Andrew factored the expression 20x^312x^2+8x as 4x(5x^212x^2+8x). But when Melissa applied the distributive law and multiplied out 4x(5x^212x^2+8x),she got 20x^348x^3+32x^2; thus, Andrew's solution does not appear to check. Why is that? Please help Andrew to understand this better. Explain your reasoning and correctly factor the original expression, if possible. If the expression is prime, state this.

algebra 
Reiny,
Andrew messed up, should have been
= 4x(5x^2  3x + 2)