Answer: No real solutions
Note: this is assuming you haven't reached complex numbers yet
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Step-by-step explanation:
The given equation 13u^2+23u = -112 is the same as 13x^2+23x = -112
and we can add 112 to both sides getting 13x^2+23x+112 = 0
We see the equation is in the form ax^2+bx+c = 0
The discriminant is
D = b^2 - 4ac
D = 23^2 - 4(13)(112)
D = -5295
The negative discriminant means there are no real number solutions.
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Extra info:
If D = 0, then there would be exactly one real number solution.
If D > 0, then there would be two distinct real number solutions.