Answer:
y=7
Step-by-step explanation:
Multiply each equation by the value that makes the coefficients of y opposite.
3x+y=4
(−1)⋅(2x+y)=(−1)(5)
Simplify.
3x+y=4
−2x−y=−5
Add the two equations together to eliminate y from the system.
3x+y=4
+−2x−y=−5
x = −1
Substitute the value found for x into one of the original equations, then solve for y
3(−1)+y=4
Multiply 3 by −1
−3+y=4
Move all terms not containing y to the right side of the equation.
Add 3 to both sides of the equation.
y=4+3
Add 4 and 3
y=7
