Elimination method?
Let's do it like this
Align the two equation
7x - 4y = 19
+17x - 2y = -31
-------------------------
Let's begin with
19 + (-31)
unlike terms will be subtracted and take the sign of the bigger number
So it will be -12
Next
-4y + -2y
Like terms will be added and copy the sign of the two
So it will be -6y
Lastly,
7x + 17x
Add
So it will be 24x
We may now combine the three
24x - 6y = -12
That's it
We may divide all by 6 to simplify
(24x - 6y)/6 = -12/6
So it will be
4x - y = 2
That's it again
I hope it helps
