This week in Precalc, we continued our unit on “Rational Expressions and Equations.” I actually am really enjoying the unit.

We reviewed adding and subtracting Rational Expressions and I want to review the ones with non-variable and variable denominators.

The first step is to determine the lowest common denominator (LCD)

Then you rewrite each fraction as an equivalent fraction including the lowest common denominator

After that, you combine numerators by adding/subtracting

Lastly, you reduce the fraction, if possible

So basically, it’s exactly what we have been doing with fractions for the past few years but this year, we are just adding variables in the denominators, making it a little more difficult, nothing we can’t handle though.

Here are a two examples for a non-variable fraction and one with a variable in the denominator…