Substitution
 

2x+3y=5
x=4-2y

2x+3y=5
x=4-2y
When you are doing sustitution, you need to first get one of the variable on a side by itself. In this case the "x" is already on a side by itself.
2(4-2y)+3y=5
Next, you want to "substitute" the equation with the "x" on the side by itslf into the other equation.
8-4y+3y=5
Now, distribute the 2 to what is inside the parentheses.
8-y=5
Then, combine like terms.
-y=-3
You can't have a negative variable (y), so you must divide both sides by negative 1.
y=3
Now, you must plug the "y" back into the equation that you did't use to solve the first equation. ( that would be 2x+3y=5)
2x+3(-3)=5
Multiply the -3 and the 3.
2x+(-9)=5
Now, combine like terms.
2x=14
Divide to get the variable by itself. 
x=7
Then, put the "x" and "y" into a coordinate pair.
(7,3)
The final answer.

 

The Final Answer:
(7,3)
 
 

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