# Parabola

### Parabola

Hi, I'm trying to work out the x-intercepts of the parabola of the quadratic equation y = - x^2/8 + 11x/8 + 3/2. Anyone got any advice please, thanks.
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### Re: Parabola

You have to solve the equation
$$- \frac{x^2}{8} + \frac{11x}{8} + \frac32 = 0$$

Multiply the both sides by 8
$$- x^2 + 11x + 12 = 0$$

$$D = 12^2 - 4\cdot 11 \cdot(-1) = 144 + 44 = 188$$

The roots are
$$x_{1,2} = \frac{-11 \pm \sqrt{188}}{-2}$$
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