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4 votes
Solve the system using substitution.
x + 3y = 3
3y - 2x = 12
([?], [ ])

User TheRonin
by
4.3k points

2 Answers

3 votes

Answer:

(-3,2)

Explanation:

4 votes

Answer: (-3,2)

Explanation:

Solving by substitution involves taking one of the equations and basically plugging it into the other.

I would start by taking the first equation and rearranging it to equal a variable. It will be easier to solve using this equation as the x variable is already isolated.

Take:
x+3y=3

Subtract 3y to the other side:
x=3-3y

Now plug this equation in for the value x into the other equation like so:


3y-2(3-3y)=12

Now there is only one variable to solve in this new equation. Solve for the value y.

Distribute -2:
3y-6+6y=12

Combine Like Terms:
9y-6=12

Add 6 to both sides to cancel:
9y=18

Divide by 9 to both sides to cancel 9:
y=2

So the value y=2.

Now we can plug the value of y back into either equation to now solve for x.


x+3(2)=3


x+6=3


x=-3

Now you have the point (-3,2)

You can check your answers if you would like.

User Kralyk
by
3.9k points