# How do you solve by substitution 5x - 4y = 9 and x - 2y = -3?

Jun 24, 2015

I found:
$x = 5$
$y = 4$

#### Explanation:

Collect $x$ from the second equation:
$x = 2 y - 3$
Substitute for $x$ into the first equation:
$5 \left(2 y - 3\right) - 4 y = 9$
$10 y - 15 - 4 y = 9$
$6 y = 24$
$y = 4$
Substitute this back into the second equation:
$x = 8 - 3 = 5$