An air-conditioning company counted 56 invoices at the end of the month. They charge $450 for a new installation and $75

Mathematics

1 answer:

k0ka [10]2 years ago

8 0

Answer:

14 installatons

42 service calls

Step-by-step explanation:

Let x = no. of new installations

y = no. of service calls

(1) x + y = 56 (2) 450x + 75y = 9450

y = 56 - x 450x + 75(56 - x) = 9450

450x + 4200 - 75x = 9450

375x = 5250

x = 14 installatons

y = 56 - 14 = 42 service calls

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A billboard is 27 feet high and casts a 36-foot shadow at noon. At the same time, a fir tree next to the billboard casts a 48-fo

Archy [21]

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Step-by-step explanation:

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