Answer:
84
Step-by-step explanation:
Arc length = rθ [r = radius of the circle, θ = central angle in radians] ⇒
2π = 8*θ ⇒ θ = 2π/8 = π/4
y = x² - 4x + 8
4x + y = 12
4x + y = 12
4x + (x² - 4x + 8) = 12
x² + 4x - 4x + 8 = 12
x² + 8 = 12
- 8 - 8
x² = 4
x = ±2
4x + y = 12
4(2) + y = 12
8 + y = 12
- 8 - 8
y = 4
4x + y = 12
4(-2) + y = 12
-8 + y = 12
+ 8 + 8
y = 20
(x, y) = (2, 4) and (-2, 20)
