Example

Try It 7.53: Simplifying b−3bb+52b+5+1b−5\frac{b-\frac{3b}{b+5}}{\frac{2}{b+5}+\frac{1}{b-5}} by Writing it as Division

To simplify the complex rational expression b−3bb+52b+5+1b−5\frac{b-\frac{3b}{b+5}}{\frac{2}{b+5}+\frac{1}{b-5}} by writing it as division, follow these steps:

Step 1. Simplify the numerator and denominator. In the numerator, the common denominator is b+5b+5. Rewrite bb as b(b+5)b+5\frac{b(b+5)}{b+5}. Subtracting gives b(b+5)−3bb+5=b2+5b−3bb+5=b2+2bb+5\frac{b(b+5)-3b}{b+5} = \frac{b^2+5b-3b}{b+5} = \frac{b^2+2b}{b+5}. In the denominator, the common denominator is (b+5)(b−5)(b+5)(b-5). Rewrite as 2(b−5)(b+5)(b−5)+1(b+5)(b+5)(b−5)=2b−10+b+5(b+5)(b−5)=3b−5(b+5)(b−5)\frac{2(b-5)}{(b+5)(b-5)} + \frac{1(b+5)}{(b+5)(b-5)} = \frac{2b-10+b+5}{(b+5)(b-5)} = \frac{3b-5}{(b+5)(b-5)}. The complex fraction becomes: b2+2bb+53b−5(b+5)(b−5)\frac{\frac{b^2+2b}{b+5}}{\frac{3b-5}{(b+5)(b-5)}}.

Step 2. Rewrite as fraction division. Replace the main fraction bar with a division symbol: b2+2bb+5÷3b−5(b+5)(b−5)\frac{b^2+2b}{b+5} \div \frac{3b-5}{(b+5)(b-5)}

Step 3. Multiply by the reciprocal and simplify. Change the division to multiplication by the reciprocal: b2+2bb+5⋅(b+5)(b−5)3b−5\frac{b^2+2b}{b+5} \cdot \frac{(b+5)(b-5)}{3b-5} Factor the numerator b2+2bb^2+2b to b(b+2)b(b+2). b(b+2)(b+5)(b−5)(b+5)(3b−5)\frac{b(b+2)(b+5)(b-5)}{(b+5)(3b-5)} Divide out the common factor of (b+5)(b+5). The simplified result is: b(b+2)(b−5)3b−5\frac{b(b+2)(b-5)}{3b-5}

0

1

Updated 2026-06-03

Contributors are:

Who are from:

Tags

OpenStax

Intermediate Algebra @ OpenStax

Ch.7 Rational Expressions and Functions - Intermediate Algebra @ OpenStax

Algebra

Related
Learn After