## Algebra: A Combined Approach (4th Edition)

In two similar triangles, the corresponding sides are in proportion. Given triangle GHI is similar to triangle JKL. Then, $\frac{GH}{JK}$ = $\frac{GI}{JL}$ = $\frac{HI}{KL}$ Substituting the values from the given figure, $\frac{12}{4}$ = $\frac{20}{\frac{20}{3}}$ = $\frac{18}{x}$ $\frac{12}{4}$ = 3 $\frac{20}{\frac{20}{3}}$ = $\frac{20(20)}{3}$ = 3 Thus 3 = 3 = $\frac{18}{x}$ Thus c = 3 Thus x = = $\frac{18}{3}$ = 6