Answer:
look at the picture i have sent
X + y = 1
x + 3y = 9
Subtract the second equation from the first.
-2y = -8
divide both sides by -2
y = 4
Plug 4 back into either equation and solve for x.
x + y = 1
x + 4 = 1
subtract 4 from each side
x = -3
(-3, 4)
-9-(-12)=-9+12=3
-9-12=-9+(-12)=-21
4x + 8y = 40
4x + 8(0.8) = 40
4x + 6.4 = 40
40 - 6.4 = 33.6
33.6 / 4 = x
33.6 / 4 = 8.4
The answer option 2, 8.4