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
Answer:
One solution
Step-by-step explanation:
They have isolated y for you in both equations so you can plug either one into the other.
y = 3x - 1
2x + 7 = 3x - 1
isolate the x
7 = x - 1
x = 8
Go back to the original and plug 8 into x to get y.
y = 2 (8) + 7
y = 16 + 7
y = 23
This means at (8, 23) y = 2x+7 is equal to y = 3x-1. In other words they share a point at (8, 23). This is the only solution because for any other x and y they'd not be equal.
