y = 8 -2x
x + 2 (8 - 2x) = 1
x + 16 - 4x = 1
x - 4x = -15
-3x = -15
x = 5
If x = 5, then we can substitute in...
5 + 2y = 1
2y = -4
y = -2
Now let us check that by substituting those values in to the equation
2x + y = 8
2 (5) + (-2) = 8
That is correct so we have the right values for x and y/
The unit price would be $0.20 because when you divide $3.20 by 16, that is what you would get. The equation would be
$3.20/ 16 oz. = $0.20
Graph it on graph paper then connect the dots then you can measure each side by the amount of boxes and then you take base × height ÷2
0.4 -> 4/10 (divided by 2) -> 2/5
0.35 -> 35/100 (divided by 5) -> 7/20