## Geometry: Common Core (15th Edition)

All three proportions are equal. Look at only the first two to solve for x: $\frac{x}{6}$=$\frac{x+10}{18}$ Cross Multiply: 18x=6(x+10) 18x=6x+60 12x=60 x=5 Use the last two proportions substituting 5 in for x to solve for y $\frac{x+10}{18}$=$\frac{4x}{y}$ $\frac{5+10}{18}$=$\frac{4(5)}{y}$ $\frac{15}{18}$=$\frac{20}{y}$ Cross Multiply: 15y=18(20) 15y=360 y=24