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

Mar 21, 2016

$x = y = - 1$

#### Explanation:

color(blue)(y=4x+3

color(blue)(2x+3y=-5

In the first equation substitute the value of $y$ to the second equation

$\rightarrow 2 x + 3 \left(4 x + 3\right) = - 5$

Use distributive property color(brown)(a(b+c)=ab+ac

$\rightarrow 2 x + 12 x + 9 = - 5$

$\rightarrow 14 x + 9 = - 5$

$\rightarrow 14 x = - 5 - 9$

$\rightarrow 14 x = - 14$

rArrcolor(green)(x=-14/14=-1

Substitute the value of $x$ to the first equation

$\rightarrow y = 4 \left(- 1\right) + 3$

$\rightarrow y = - 4 + 3$

rArrcolor(green)(y=-1

:.color(blue)(ul bar |x=y=-1|