Question

Which shows the expressions rewritten with the least common denominator?

7x-2/4x^2 and x-1/8x

A. 28x-8/16x^2 and 2x^2-2x/16x^2
B. 14x-4/8x^2 and 2x-2/8x^2
C. 28x^2-8x/16x^3 and 2x^3-2x^2/16x^3
D. 14x-4/8x^2 and x^2-x/8x^2

Answer 1

D. (14x-4)/(8x^2) and (x^2-x)/(8x^2)

Explanation:

The least common denominator will be 8x^2, the product of 2 and x to the highest of their powers in either of the denominators.

`\left\{(7x-2)/(4x^2),\ (x-1)/(8x)\right\}=\left\{(7x-2)/(4x^2)\cdot(2)/(2),\ (x-1)/(8x)\cdot(x)/(x)\right\}\\\\=\left\{(14x-4)/(8x^2),\ (x^2-x)/(8x^2)\right\}`