Solve the quadratic equation 2x^2 - 7x + 3 = 0.
Answer and explanation
Correct answer: D. x = 3 or x = 1/2
- Step 1: Split the middle term: 2x^2 - 6x - x + 3 = 0. Step 2. 2x(x - 3) - 1(x - 3) = 0, so (2x - 1)(x - 3) = 0. Step 3. x = 1/2 or x = 3. Answer: x = 3 or x = 1/2. Why not the others: x = -3 or x = -1/2: The signs of both roots are reversed. x = 3 or x = -1/2: Only one of the roots has the correct sign. x = 6 or x = 1: Those roots belong to x^2 - 7x + 6 = 0.
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