How to solve this problem?

2x+y=3
-2+5y=-9

1 Answer
May 14, 2018

#x=11/5 and y =(-7)/5#

Explanation:

#2x + y = 3#
#-2 + 5y = -9#

This is called a system of equations!

To solve this system of equations, we gonna use the substitution method.

So, we wanna solve #5y - 2 = -9# for #y#

#5y - 2 = -9#

Start by adding #2# on both sides

#5y - 2 + 2 = -9 + 2#

#5y = -7#

Then divide both sides by #5#

#(cancel5y)/cancel5 = (-7)/5#

#y=(-7)/5#

Now we wanna use the value of #y# to find the value of #x#.

We gonna do that by substitute #(-7)/5# for #y# in #2x + y=3#
What does that mean? It means that we gonna replace #y# by #(-7)/5# in the equation.

#2x + y = 3#

#2x + (-7)/5 = 3

Now we can add #7/5# to both sides

#2x + (-7)/5 + 7/5=3 + 7/5#

#2x = (15 + 7)/5#

#2x = 22/5#

Divide both sides by #2#

#(cancel2x)/cancel2 = 22/(5/2)#

#x = 11/5#

Thus,

The answers are: #x=11/5 and y=(-7)/5#