How do you simplify (2x)/(x^2+8x+15)-(x+3)/(x+5)?

1 Answer
Jul 6, 2017

frac(x^2+8x+9)(x^2+8x+15)

Explanation:

To simplify this one must first find the common denominator. This is found by first factoring x^2+8x+15.
This factors into (x+5)(x+3)

Next multiply the 2nd fraction by (x+3)/(x+3) to make the denominators equal.

frac(2x)(x^2+8x+15)-frac(x+3)(x+5)*frac(x+3)(x+3)

frac(2x)(x^2+8x+15)-[(x+3)(x+3)]/[(x+3)(x+5)]

(x+3)(x+3)=x^2+6x+9, so combining these,

frac(2x)(x^2+8x+15)-frac(x^2+6x+9)(x^2+8x+15)=frac(x^2+8x+9)(x^2+8x+15)