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

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Answer 1 · 2016-03-21T13:26:25

$x=y=-1$

$color(blue)(y=4x+3$

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

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

$rarr2x+3(4x+3)=-5$

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

$rarr2x+12x+9=-5$

$rarr14x+9=-5$

$rarr14x=-5-9$

$rarr14x=-14$

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

Substitute the value of $x$ to the first equation

$rarry=4(-1)+3$

$rarry=-4+3$

$rArrcolor(green)(y=-1$

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

How do you solve y = 4x + 3y = 4x + 3 and 2x + 3y = -52x + 3y = -5 using substitution?