y = x² + x - 42
x² + x - 42
x = -1 +/- √(1² - 4(1)(-42))
2(1)
x = -1 +/- √(1 + 168)
2
x = -1 +/- √169
2
x = -1 +/- 13
2
x = -1 + 13 x = -1 - 13
2 2
x = 10 x = -14
2 2
x = 5 x = -7
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y = x² + x - 42 y = x² + x - 42
y = (5)² + 5 - 42 y = (-7)² + 5 - 42
y = 25 + 5 - 42 y = 49 + 5 - 42
y = 30 - 42 y = 54 - 42
y = -12 y = 12
(x, y) = (5, -12) y = (-7, 12)