How do you solve this system of equations: #-\frac { 3} { 5} x + \frac { 1} { 2} y = - 2 and - x + y = - 3#?

1 Answer
Nov 26, 2017

#x=5\quad,\quad y=2#

Explanation:

We’ll use elimination for this one to cancel out the #y# terms, in order to first solve for #x#.

We’ll multiply the first equation by #-2#:

#-\frac{3}{5}x+\frac{1}{2}y=-2#

#\rightarrow -2(-\frac{3}{5}x+\frac{1}{2}y)=(-2)-2#

#\rightarrow \frac{6}{5}x-y=4#

Now we can add this equation to the other equation to solve for #x#:

#(\frac{6}{5}x-y=4)\quad +\quad (-x+y=-3)#

#\rightarrow \frac{1}{5}x=1#

#x=5#

Now we can plug the value of #x# into an equation to find the value of #y#:

#-x+y=-3#

#\rightarrow -5+y=-3#

#\rightarrow y=2#


Having solved for both variables, we can check our work by plugging those values into one of the equations:

#-\frac{3}{5}x+\frac{1}{2}y=-2#

#-\frac{3}{5}(5)+\frac{1}{2}(2)=-2#

#-3+1=-2#

#-2=-2#

So the answer is right.