Question

Solve each system using substitution. check your solution.
-2x+5y=19
3x-4=y

Answer 1

Answer:

$- 2x + 5y = 19 \\ \\ 3x - 4 = y \\ 3x - y = 4 \\ \\ - 2x + 5y = 19 ⟹ ⓵ \\ 3x - y = 4 ⟹ ⓶ \\ \\ - 2x + 5y = 19 ⟹ ⓵ \\ (3x - y = 4) × 5 ⟹ ⓶ \\ \\ - 2x + 5y = 19 \\15x - 5y = 20 \\ - - - - - - - - \\ 13x = 39 \\ x = \frac{39}{13} \\ \boxed{\large x = \underline{ \underline{\bf 3}}} \\ \\ - 2x + 5y = 19 \\ - 2(3) + 5y = 19 \\ - 6 + 5y = 19 \\ 5y = 19 + 6 \\ 5y = 25 \\ y = \frac{25}{5} \\ \boxed{\large y = \underline{ \underline{\bf 5}}} \\ \\ \large{\underline{\underline{Let's \: \: check \: \: the \: \: Solution}} :} \\ -2x + 5y = 19 \\ -2(3) + 5(5) = 19 \\ -6 + 25 = 19 \\ \boxed{\underline{\underline{\bf 19 = 19}}} \\ \\ 3x - 4 = y \\ 3(3) - 4 = 5 \\ 9 - 4 = 5 \\ \boxed{\underline{\underline{\bf 5=5}}}$