Engineering Board Exam Reviewer · Quadratic Equations · easy

Find the discriminant of 2x2-3x+5=0.

1. 31
2. -31
3. 49
4. -9

Answer

B. -31

Solution

b2-4ac=(-3)2-4(2)(5)=9-40=-31. Since it is negative, the roots are complex conjugates.

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