Sandra exclaims that her quadratic with a discriminant of −4 has no real solutions. Sandra then puts down her pencil and refuses to do any more work. Create an equation with a negative discriminant. Then explain to Sandra, in calm and complete sentences, how to find the solutions, even though they are not real.

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anonymous · Answer

@wolf1728  CAN U HELP

wolf1728 · Answer

In the equation 
x²  +2x + 2 = 0
the discriminant equals
b² - 4*a*c = -4
Because this requires the square root of a negative number, the solution will not be real.  There is a solution nonetheless.
Mathematicians have decided that 'i' is the square root of minus 1.
So, i² = -1.
So, the square root of -4 is sqrt(4) * sqrt(-1)
and the solutions are 2 + i and 2 -i