## Intermediate Algebra (6th Edition)

$\frac{0}{4}$ simplifies to 0 while $\frac{4}{0}$ is undefined.
Any fraction with 0 as the numerator is equal to 0, because you can't divide 0 into any other number of parts. However, you can't divide a number by 0, so $\frac{4}{0}$ is undefined.