Which expression is equivalent to 1/8x- 1/2? a. 1/8(x-1/2) b.1/8(x-1/4) c.-1/8(x-4) d. 1/8(x-4)

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: , 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: .  This of course reduces to 4.  So when we factor out 1/8, what we will have then is , choice D from above.