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3 years ago

Number 7 please! I need help badly

Mathematics

1 answer:

melamori03 [73]3 years ago

7 0

Answer:

A computer costs $225 and a printer $150.

Step-by-step explanation:

Let c be the cost of a computer and p the cost of a printer, then:

3c + p = 825

4c + 2p = 1200

Multiply the first equation by -2:

-6c - 2p = -1650

Add this to the second equation:

-2c = -450

c = 225.

Now substitute c = 225 in the first equation:

3*225 + p = 825

p = 825 - 675 = 150.

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Answer:

See Explanation

Step-by-step explanation:

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