Answer :
12 = x² - x
12 - 12 = x² - x - 12
0 = x² - x - 12
x² - x - 12 = 0
x = -(-1) +/- √((-1)² - 4(1)(-12))
2(1)
x = 1 +/- √(1 + 48)
2
x = 1 +/- √(49)
2
x = 1 +/- 7
2
x = 0.5 +/- 3.5
x = 0.5 + 3.5 x = 0.5 - 3.5
x = 4 x = -3
12 - 12 = x² - x - 12
0 = x² - x - 12
x² - x - 12 = 0
x = -(-1) +/- √((-1)² - 4(1)(-12))
2(1)
x = 1 +/- √(1 + 48)
2
x = 1 +/- √(49)
2
x = 1 +/- 7
2
x = 0.5 +/- 3.5
x = 0.5 + 3.5 x = 0.5 - 3.5
x = 4 x = -3