Find the discriminant of .
Answer and explanation
Correct answer: D. 81
- Step 1: For a quadratic equation , the discriminant is defined as . Here, , , and .
- Step 2: Substitute the coefficients into the discriminant formula: .
- Step 3: Since (), the quadratic equation has two distinct real roots.
Answer
81.
Why not the others: -63, -81 and 45 do not fit.
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