What is0.4x - 0.1y = 2

If you want to isolate y then: y=-20+4x

To solve the set of equations given above, we can use the substitution method where we substitute one equation to the other and solving for one variable. We do as follows:

0.4x - 0.1y = 2

x = 5 + 0.25y

0.2x + 0.5y = 1

0.2 (5 + 0.25y) + 0.5y = 1

y = 0

x = 5

Therefore, the correct answer from the choices is option A, (5,0).