For those who are too lazy to read instructions in the HELP section how to use the scientific calculator:
3(x-4)^2+12=18 => 3(x^2 + 16 - 8x) - 6 = 0 => 3x^2 + 48 - 24x - 6 = 0 => 3x^2 - 24x + 42 = 0 --> D = 12^2 - 3*42 = 144 - 126 = 18
x = (12 +- sqrt(18))/3 = (12 +- 3sqrt(2))/3 = 3(4 +- sqrt(2))/3 = 4 +- sqrt(2) solve(3(x-4)^2+12=18, x)
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