Question

Solve the following system of equations:

-2x + y = 1
-4x + y = -1

Answer 1

1,3

Answer 2

Have you done anything for this?

Answer 3

-2x + y = 1
-4x + y = -1 --- (-1)
--------------
-2x + y = 1
4x - y = 1 (result of multiplying by -1)
--------------add
2x = 2 -- divide by 2 on both sides
x = 1
now sub 1 in for x in either equation to find y
-2x + y = 1
-2(1) + y = 1
-2 + y = 1 -- add 2 to both sides
y = 1 + 2
y = 3

check...
-4x + y = -1
-4(1) + 3 = -1
-4 + 3 = -1
-1 = -1 (correct)

solution is (1,3)