Adding and Subtracting Rational Expressions
Don’t you hate it when you have too many rational expressions—or too few? Thank goodness for addition and subtraction. We don’t know what we’d do without those two.
|Basic Operations||Addition and Subtraction|
Of course, we're going to have to simplify things...
We'll be representing the unsplicing with the following equation...
Five x over x plus three minus x minus three over x plus three.
Duck DNA is mathematically represented by x minus three over x plus three. [Duck and a platypus with a DNA helix spinning behind them]
Since they have a common denominator…
…we can just squish them together into five x minus x minus three in parentheses, all [Hands squish the equation together]
over x plus three.
Getting rid of the parentheses, this breaks down into five x minus x plus three all over [Parentheses looks upset]
x plus three.
So the answer is four x plus three over x plus three.
This happens to be the DNA code for that kid from the Sixth Sense. [Kid with a duck on his knee]
We always wondered what happened to him. [Duck lays an egg]