9/x+2 minus 8/x-7

When adding and subtracting fractions, you need to get the least common denominator.

When deciding on the least common denominator, you need one of each term.

9/(x + 2) - 8/(x - 7) {the least common denominator is (x + 2)(x - 7)}

= 9(x - 7) / (x + 2)(x - 7) - 8(x + 2) / (x + 2)(x - 7) {got the least common denominator}

= 9x - 63 / (x + 2)(x - 7) - 8x + 16 / (x + 2)(x - 7) {used distributive property in numerators}

**x - 79
**

-------------- {combined numerators and put over common denominator (watch signs)}

**(x + 2)(x - 7)***- Algebra House*
**
**