Answer:
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Step-by-step explanation:
Hope it helps
X = 47 + 9y
xy = 1860
y(47 + 9y) = 1860
47y + 9y² = 1860
9y² + 47y - 1860 = 0
> using a quadratic equation solver on a calculator but you can also use the quadratic equation = [-b+/- √(b²-4ac)]/(2a)
> only integer solution is x = 12
12y = 1860
y = 155
integers are 12 and 155
y = 80x - 60
Answer is B. y = 80x - 60
Double check:
When x = 1, y = 80(1) - 20 = 80 -60 = 20
When x = 2, y = 80(2) - 20 = 160 -60 = 100
When x = 3, y = 80(3) - 20 = 240 -60 = 180
When x = 4, y = 80(4) - 20 = 320 -60 = 260
When x = 5, y = 80(5) - 20 = 400 -60 = 340
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