Use the quadratic formula to solve $2x^2 - x - 6 = 0$.
A$x = 2$ and $x = -3/2$
B$x = -2$ and $x = 3$
C$x = 1/2$ and $x = 6$
D$x = -1$ and $x = 6$
Answer & Solution
Correct answer: A. $x = 2$ and $x = -3/2$
With $a = 2$, $b = -1$, $c = -6$, the discriminant is $b^2 - 4ac = 1 + 48 = 49$. So $x = \frac{1 \pm 7}{4}$, giving $x = 2$ and $x = -3/2$. The factored form $(2x+3)(x-2) = 0$ confirms the same two roots.
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