Question

Which expression is equivalent to 1/8x- 1/2?

Answer 1

This is done by factoring.  1/8 is smaller than 1/2, so we can factor a 1/8 out of 1/2.  This is what that looks like: $\frac{ \frac{1}{2} }{ \frac{1}{8} }$, because factoring after all is a form of division.  When we divide a fraction by a fraction, we bring the lower fraction up and flip it to multiply, giving us this: $\frac{1}{2} * \frac{8}{1}$.  This of course reduces to 4.  So when we factor out 1/8, what we will have then is $\frac{1}{8} (x-4)$, choice D from above.