The answer is (4,1)
Explanation: You have to make either the number with the variable x or y in front of it in the 1st equation to match the number with the variable x (if x is going to match) or y (if y is going to match).
3x+4y=16 (4)
-4x-3y=-19 (3)
12x+16y=64
-12x-9y=-57
7y=7
y=7
Then you plug in your y in the two equations and solve for x.
3x+4(1)=16
-4x-3(1)=-19
3x+4=16
-4x-3=-19
3x+4-4=16-4
-4x-3+3=-19+3
3x=12
-4x=-16
3x/3=12/3
-4x/-4=-16/-4
x=4
x=4
