# How do you evaluate #\frac { 3x - 21} { 6x - 42}#?

##### 2 Answers

#### Explanation:

Notice that the denominator is two times the numerator.

Even if you don't notice that, you should notice that you can factor out a 2 from the denominator:

And now you've got an identical 3x-21 term in both numerator and denominator that cancels out, giving:

#### Explanation:

First we see that both terms in the denominator are divisible by

Since two is a common factor between the two terms, we can

Simplifying: