## Algebra 1

To simplify this expression, we start by simplifying the numerical part of the fraction. The $\frac{63}{7}$ part of $\frac{63ab}{7a}$ simplifies to $9$, giving $\frac{9ab}{a}$. Finally, the a cancels out because there is one in the numerator and one in the denominator, giving 9b. $9b\ne9ab$.