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