Stefan bought 3 hamburgers and 4 fries for a total cost of $26.50.
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Step-by-step explanation:
system of Linear Equations 2 variables
hamburger = x
fries = y
Stefan
3x + 4y = $26.5
Nancy
4x + 2y = $29.5
elimination
3x + 4y = $26.5 | ×1 |
4x + 2y = $29.5 | ×2 | -
3x + 4y = $26.5
8x + 4y = $59. -
-5x = $-32,5
x = $-32,5 ÷ -5
x = hamburger = $6.50
I hope this help