For the following system, if you isolated x in the first equation to use the Substitution Method, what expression would you substitute into the second equation?

-x - 2y = -4
3x + y = 12

Question

For the following system, if you isolated x in the first equation to use the Substitution Method, what expression would you substitute into the second equation?

-x - 2y = -4
3x + y = 12

whpalmer4 · Answer

$$-x-2y=-4$$You want x all by itself, and you want it to be +x, not -x, so I would suggest adding x to both sides, and adding 4 to both sides.

whpalmer4 · Answer

you'll get an equation with x on the right side instead of left, but because they are equal, you can reverse the equation.

anonymous · Answer

2y = -4 + x ?

whpalmer4 · Answer

No.  

$$-x-2y-4$$Add x to both sides of that, what do you get?

No need to tag me, if I've ever responded to the question, I'll get a notification when someone does anything.

whpalmer4 · Answer

ah, 
$$-x-2y= -4$$

anonymous · Answer

I dont know? brain isnt funtioning right today.. Sorry

whpalmer4 · Answer

Come on.  $$-x-2y=-4$$Add $x$ to each side:
$$-x - 2y + x = -4 + x$$simplify that

whpalmer4 · Answer

You do that.