What is the y-coordinate of the solution of the system?
{ x + y = 3
{ 4x - y = -38

Question

What is the y-coordinate of the solution of the system?
{ x + y = 3
{ 4x - y = -38

fortytherapper · Answer

Let's first rearrange each equation to where it says y = ______

anonymous · Answer

Alright i have no clue what y = lol

mathstudent55 · Answer

Because both equations are written in the same form, and they line up perfectly, and because you have y in one and -y in the other, just use the addition method and add the equations. The y's will cancel out, and you'll end up with a single equation in x. Then solve for x. That's all you need to do since all they ask for is the x value of the solution.

fortytherapper · Answer

Like for the first one

$$x + y = 3$$

Subtracting x from both sides means doing this:

$$(x-x)+y=3-x$$

x and -x cancel out, giving you

$$y = 3-x$$

anonymous · Answer

Ok!

fortytherapper · Answer

How would you start the second one?

anonymous · Answer

Y = 4x?

mathstudent55 · Answer

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