8 slices of pizza and 5 sodas cost $36.50. 4 Slices of pizza and 10 sodas cost $37. How much does a slice of pizza cost? How much does a sod

Question

8 slices of pizza and 5 sodas cost $36.50. 4 Slices of pizza and 10 sodas cost $37. How much does a slice of pizza cost? How much does a soda cost?

PLEASE HELP

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bonexptip 5 years 2021-08-29T23:56:10+00:00 1 Answers 53 views 0

Answers ( )

  1. Orla
    0
    2021-08-29T23:57:28+00:00
    Reply

    Step-by-step explanation: If we use the variable p to represent our pizzas and s to represent our sodas, if our first equation states than 8 slices of pizza and 5 sodas cost $36.50, that’s 8p + 5s = 3650.

    Notice that I expressed cost in terms of cents so

    that we can avoid having to deal with decimals.

    In our second equation, 4 slices of pizza and

    10 sodas cost $37, that’s 4p + 10s = 3700.

    Now let’s rewrite our two equations on top of one another.

    8p + 5s = 3650

    4p + 10s = 3700

    To solve this system of equations, I would use addition.

    I would multiply the bottom equation by -2

    to create a situation where our p’s will cancel.

    When we do that, we get -8p – 20s = -7400.

    Now rewrite the equations once again ~

    8p + 5s = 3650

    -8p – 20s = -7400

    Now add the equations together.

    So we have -15s = -3,750.

    Divide both sides by -15 and s = 250.

    Remember that I expressed cost in terms of cents so

    since s = 250, it really means that a soda is $2.50.

    Now just plug an s back in for the s in one equation.

    When we do this, we find that p = 300.

    So a pizza is $3.00

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