## Algebra 1

Set up a ratio to find the missing length. Since the triangles are similar, the ratio between the lengths of corresponding sides is the same. $\frac{5}{9}=\frac{7}{x}\longrightarrow$ cross multiply $5x=63\longrightarrow$ divide each side by 5 $5x\div5=63\div5\longrightarrow$ divide $x=12\frac{3}{5}$