# What are the zeros of the function y=2x^2-3x-20, and why?

##### 1 Answer
Apr 4, 2018

${x}_{1} = 4 \mathmr{and} {x}_{2} = \frac{5}{2} = 2.5$

#### Explanation:

The zeros, or also know as interceptions of the x-axis, can be determinated by $y = 0$

0=2x^2-3x-20|:2
$0 = {x}^{2} - \frac{3}{2} x - 10$

$0 = {\left(x - \frac{3}{4}\right)}^{2} - \frac{9}{16} - 10$
$0 = {\left(x - \frac{3}{4}\right)}^{2} - \frac{169}{16} | + \frac{169}{16} | \sqrt{}$
$\pm \frac{13}{4} = x - \frac{3}{4} | + \frac{3}{4}$
$x = \frac{3}{4} \pm \frac{13}{4}$
${x}_{1} = 4 \mathmr{and} {x}_{2} = \frac{5}{2} = 2.5$