13. x + y = 40
2.25x +1.75y = 83.50
Multiply the first equation by -2.25
So you get -2.25x + -2.25y = -90
So now your equations are -2.25x + -2.25y = -90
2.25x +1.75y = 83.50
And add them together -------------------------------
-.5y = -6.5
÷-.5 ÷-.5
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y = 13
Now that you know y= 13 then u can plug it into any of the equations
i use x + y = 40 since it's easier
So plug in 13 for y
You should get x + 13 = 40
-13 -13
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x = 27
So 27 hotdogs and 13 popcorns were purchased.