Solve the system: y = 4x + 6 -5x - y = 21

Mathematics

1 answer:

Hitman42 [59]2 years ago

6 0

Substitute y in second equation
-5x-(4x+6)=21
-9x-6=21
9x+6=-21
9x=-27
X=-3
Solve for y:
Y=4(-3)+6
Y=-6

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\\
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Hi there!

Your question:

Sales fall from 300 per week to 270 per week what's the percentage change?

My answer:

The formula for calculating percent change is as follows:

[(y2 - y1)/y1]*100=your percent change

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Hope this helps! Let me know if it's incorrect so I can fix it:)

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