How do you solve 4x + 5y = 11 and y = 3x - 13?

Question

6358 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2015-10-14T06:37:43

The solution is
$x=4,y=-1$

$4x + 5y = 11$ ...equation $1$
$y =color(blue)( 3x - 13$ ....equation $2$

Solving by substitution :

Substituting equation $2$ in $1$

$4x + 5y = 11$
$4x + 5color(blue)(( 3x - 13) = 11$

$4x + 15x - 65 = 11$

$19x = 11+65$

$19x = 76$

$x=76/19$

$color(blue)(x=4$

Finding $y$ by substituting $x$ in equation $2$ :

$y = 3x - 13$

$y = 3*4 - 13$

$y = 12 - 13$

$color(blue)(y=-1$