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

x = - $\frac{9}{5}$ y = $\frac{3}{5}$
10x - 5y = -21 x + 3y = 0 to the second equation ,minus 3y to both sides x + 3y - 3y = 0 - 3y x = - 3y simplify 10 ( -3y ) - 5y = -21 substitude x to the first equation - 30y - 5y = -21 -35y = -21 simplify $\frac{-35y}{-35}$ = $\frac{-21}{-35}$ y = $\frac{21}{35}$ divide by -35 both sides y = $\frac{3}{5}$ divide by 7 both sides x = -3y x = -3 ( $\frac{3}{5}$) x = - $\frac{9}{5}$