Equations. Solve for y or just solve. 2x-4y=12 and -3y=3x-9.

Just want to know the answer and step by step.

so for the first one 2x-4y=12 to start subtract 2x from both sides so it would be -4y=-2x+12 for the next step in order to get the y by itself you hace to divide by -4. make sure you also divide the whole right side by -4 though! so the result would be y=2/4x-3 but you have to reduce it so it would end up being y=1/2x-3 ... the second one is easier... since the x and y are on the same side all you have to do is divide both sides by -3... so the result would be y=-1x+3

Before we start, simplify both equations. The first one can be divided by 2 throughout, and the second equation by 3. Here are the revised equations:
x - 2y = 6
-y = x - 3

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Here's how to solve the problem using the SUBSTITUTION method. We'd normally find what "x" is in terms of "y" from one of the given equations, then make a substitution in the second equation.

In this case, the second equation already has x and y on opposite sides of the equals sign, so it's pretty much ready to go. Multiply both sides by -1 to get it into a convenient form:
y = -x + 3

Now use "-x + 3" instead of "y" in the first equation:
x - 2y = 6
x - 2(-x + 3) = 6

Distribute the 2. Remember that minus times minus equals plus.
x + 2x - 6 = 6
3x - 6 = 6
3x = 12
x = 4

Now replace "x" with "4" in either original equation:
-y = x - 3
-y = 4 - 3
-y = 1
y = -1

SOLUTION: x = 4, y = -1

Note that if you plotted both lines on an x-y grid, they'd intersect at (4, -1)

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Another way to solve this is by using the ELIMINATION method. Add the two entire equations together:
x - 2y = 6 +
-y = x - 3
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x - 3y = x + 3

Subtract x from both sides: