Answer: There are two points of intersection (2, 4) and (-4, -2)
Explanation:
x - y + 2 = 0 → x = y - 2
Use Substitution Method:
x² + y² = 20
(y - 2)² + y² = 20 replaced x with (y - 2)
y² - 4y + 4 + y² = 20 expanded (y - 2)²
2y² - 4y + 4 = 20 added like terms
2y² - 4y - 16 = 0 subtracted 20 from both sides
y² - 2y - 8 = 0 divided both sides by 2
(y - 4)(y + 2) = 0 factored
y - 4 = 0 and y + 2 = 0 applied Zero Product Property
y = 4 and y = -2
Input the y-values into x = y - 2 to solve for x.
y = 4; x = 4 - 2 y = -2; x = -2 - 2
x = 2 x = -4
(2, 4) (-4, -2)