Question

Solve, using linear combination
3x + y = 4
2x + y = 5

A.

(–3, 13)








B.

(–1, 7)








C.
(0, 4)







D.

(–3, 12)

Answer 1

B?

Answer 2

Begin by isolating the variable y on both functions.

y = -3x + 4
y = -2x + 5

Answer 3

Now since they are both equal to each other, you can do as follow:

-3x + 4 = -2x + 5

Answer 4

x = -1. So Yes, B is correct.