Question 243294
slove the system by the addition method 
{{{system(x+4y=5,2x+3y=0)}}}
<pre><font size = 4 color = "indigo"><b>
To make the y's cancel, multiply both sides of the first equation
by -3 and both sides of the second equation by 4

{{{system(-3(x+4y)=-3(5),4(2x+3y)=4(0))}}}

Simplify:

{{{system(-3x-12y=-15,""+8x+12y=0)}}}

Add the equations term by term and the y terms cancel
out:

{{{5x=-15}}}

{{{x=-3}}}

Start over:

{{{system(x+4y=5,2x+3y=0)}}}

To make the x's cancel, multiply both sides of the first equation
by -2 and leave the second equation as it is:

{{{system(-2(x+4y)=-2(5),2x+3y=0)}}}

Simplify:

{{{system(-2x-8y=-10,""+2x+3y=0)}}}

Add the equations term by term and the x terms cancel out:

{{{-5y=-10}}}

{{{y=2}}}

Edwin</pre>