Question

can someone please help me answer this question? I could really use some help...
Question~
Solve the systems using the Substitution method.
-3x + y = 0
3x - y = -12

Answer 1

To use the substitution method, the first thing you need to do is to solve one equation for one variable.

Answer 2

Use the first equation.
Can you solve it for y?

Answer 3

Since you have -3x on the left side, but you want y alone, add 3x to both sides.
What do you get?

Answer 4

-3x + y = 0-3x?
y=0?

Answer 5

No.
You need to add 3x to both sides.
-3x + y = 0
Add 3x to both sides:
-3x + 3x + y = 0 + 3x
y = 3x

Answer 6

Now you have the first equation solved for y.
Now we do the substitution step.
Since y = 3x, where we see y in the second equation, we substitute y with 3x.

Answer 7

oo ok I'm sorry I thought I had to subtract

Answer 8

Here is the second equation.
3x - y = -12
We see y on the left side.
We now rewrite the equation, substituting y with 3x.
3x - 3x = -12
You see that y was replaced by 3x?

Answer 9

yes sir/ma'am

Answer 10

Now we simplify the left side.
Since both terms on the left side have only the variable x, they are like terms.
We can combine them together.
3x - 3x = 0, so we write:

3x - 3x = -12
0 = -12

Now we got to a false statement of equality.
0 in not equal to -12.

Since after doing several steps correctly we got to a false statement, that means the system of equations has no solution.

Answer 11

Answer: no solution

Answer 12

oh ok, thank you soo much!! you're a great help!

Answer 13

You're welcome.