I guess what you need to know is where do the two equations meet.
Start by subtracting the bottom from the top. 2x will than cancel out.
0.5 y = 35 Divide by 0.5
y = 35 /0.5
y = 70
Now you can get x.
Put 70 in for y into the second equation.
2x +3*70 = 320
2x + 210 = 320 Subtract
2x = 320 - 210
2x = 110 Now divide by 2
x = 55
Check
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You should check these.
2*55 + 3.5*70 =? 355
110 + 245 =? 355
355 =! 355
It does check out.