y = -x² + 4x + 5
-x² + 4x + 5 = 0
x = -4 +/- √(4² - 4(-1)(5))
2(-1)
x = -4 +/- √(16 + 20)
-2
x = -4 +/- √(36)
-2
x = -4 +/- 6
-2
x = -4 + 6 x = -4 - 6
-2 -2
x = 2 x = -10
-2 -2
x = -1 x = 5
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y = -x² + 4x + 5
y = -(-1)² + 4(-1) + 5
y = -1 - 4 + 5
y = -5 + 5
y = 0
(x, y) = (-1, 0)
or
y = -x² + 4x + 5
y = -(5)² + 4(5) + 5
y = -25 + 20 + 5
y = -5 + 5
y = 0
(x, y) = (5, 0)