John sold 10 hamburgers and 14 cheeseburgers.
Step-by-step explanation:
Given,
Cost of one hamburger = $3
Cost of one cheeseburger = $3.50
Total burgers sold = 24
Total revenue earned = $79
Let,
Number of hamburgers sold = x
Number of cheeseburgers sold = y
According to given statement;
x+y=24 Eqn 1
3x+3.50y=79 Eqn 2
Multiplying Eqn 1 by 3

Subtracting Eqn 3 from Eqn 2

Dividing both sides by 0.50

Putting y=14 in Eqn 1

John sold 10 hamburgers and 14 cheeseburgers.
Keywords: linear equation, elimination method
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