Question

At the taco truck an order of 1 taco and 3 quesadillas cost $ 26.50. An order if 3 tacos and 1 quesadilla cost $19.50. for 5 tacos and 1 quesadilla. What is the cost of one taco and the cost of one quesadilla?

Answer 1

The cost of 1 taco = $4

The cost of 1 quesadilla = $7.50

Explanation:

Let the cost of tacos be x and the cost of quesadillas be y.

Given condition:

x + 3y = 26.50 ------------------(1)

3x + y = 19.50 -------------------(2)

Multiply Eq. (2) by 3

3(3x + y) = 19.50 * 3

9x + 3y = 58.5 -----------------(3)

Subtract Eq. (3) from (1)

x + 3y - 9x - 3y = 26.50 - 58.50

x - 9x = -32

-8x = -32

8x = 32

Divide 8 to both sides

x = $4

Put x = 4 in (1)

4 + 3y = 26.50

Subtract 4 to both sides

3y = 26.50 - 4

3y = 22.50

Divide 3 to both sides

y = $7.50

So,

The cost of 1 taco = $4

The cost of 1 quesadilla = $7.50

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