how do you solve equations that have more than one variable???

Question

anonymous · Answer

You need the same amount of equations as unknowns for the system to be sovlable.

anonymous · Answer

@gethzee nvm that guy, he's the moderator's problem now. Do you have any actual problems so I can show you how to solve one?

anonymous · Answer

@gezimbasha Hehh , (: 
yes its 2x+3/7=9 Solve for y .

anonymous · Answer

Are you sure, it looks like you're missing the y link there. Maybe it is solve for x? Or is there another equation involved?

anonymous · Answer

@gezimbasha Yes I'm sure, that's all there is its actually a bunch of them in a worksheet im supposed to solve for y in all of them but that one is the hardest all it says is 2x + 3y/7 = 9

anonymous · Answer

Oh ok, so there's the y there. Now to solve this, all you need to do is move everything that is not y from the left side to the right side. It can be done this way:
$$2x+\frac{3y}{7}=9$$Multiply by 7$$14x+3y=63$$Subtract 14x$$3y=63-14x$$Divide by 3.$$y=\frac{63-14x}{3}$$

anonymous · Answer

@gezimbasha OMG that was easy, obviously my teacher sucks at teaching (x Thanks A lot . I understand now ! :D

anonymous · Answer

@gezimbasha I mean all you do is the opposite of what it is , but what if its 3x-y=12 I dont know what would I do with the " -y " am i supposed to add it even when i have to solve for it ?

anonymous · Answer

Just multiply by (-1) both sides of the equations. Then you will get a (-) sign on the right instead of infront of y.

anonymous · Answer

Mkkay, so the answer would be 
-4/x ?