Question

at a restaurant the cost for 2 breakfast tacos and 2 small glasses of milk is $10. The cost for 5 tacos and 3 small glasses of milk is $21. what is the cost of a taco and a small glass of milk?

Answer 1

Answer:

$3 and

$2

Step-by-step explanation:

Let the taco be x and a small glass of milk be y.

The cost of 2 tacos and 2 glasses of milk = $10

That’s 2x + 2y = 10

5 tacos and 3 small glasses of milk = $21

That’s 5x + 3y = 21

We have two equations

2x + 2y = 10

5x + 3y = 21

Multiply equation 1 by 5 and equation 2 by 2

5 x 2x + 5 x 2y = 10 x 5

2 x 5x + 2 x 3y = 21 x 2

10x + 10y = 50

10x + 6y = 42

Subtract equation two from equation on

4y = 8

Divide both sides by 4

y = 8/4

= 2 = $2

Now substitute 2 for y in any of the equations to get x.

Using equation 1 , we have

2x + 2(2) = 10

2x + 2 x 2 = 10

2x + 4 = 10

Subtract 4 from both sides

2x + 4 - 4 = 10 - 4

2x = 6

Divide both sides by 2

x = 6/2

= 3 = $3

A taco costs $3 while a glass of milk costs $2