<h3>
Answer: y - 1 = 3(x - 2)</h3>
Explanation:
The point-slope form is this general template
y - y1 = m(x - x1)
We replace m with the given slope 3, so we get to this
y - y1 = 3(x - x1)
Then replace the given point (x1, y1) with (2, 1) to end up with
y - 1 = 3(x - 2)
X² + y² = 225
x - 7y = -75
x = 7y - 75
x² + y² = 225
(7y-75)² + y² = 225
(7y - 75)(7y - 75) + y² = 225
49y² - 525y - 525y + 5625 + y² = 225
50y² - 1050y + 5400 = 0
50(y² - 21y + 108) = 0
y² - 21y + 108 ⇒ (y - 12)(y - 9)
x = 7(12) - 75
x = 84 - 75
x = 9 ⇒ (9,12)
x = 7(9) - 75
x = 63 - 75
x = -12 ⇒ (-12,9)
(f-g)(x) = x²+6x - (7-x)
(f-g)(x) = x² + 6x - 7 + x
(f-g)(x) = x² + 7x - 7
(f-g)(9) = 9² + 7*9 - 7
(f-g)(9) = 81 + 63 - 7
(f-g)(9) = 137
I would pick C sorry if it’s wrong