Quadratic equation roots

$2x^2 + 5x + 2 = (2x + 1)(x + 2)$

To find the roots of quadratic equations, you should use this quadratic formula. It is $\displaystyle \frac{-b \pm \sqrt{b^2-4ac}}{2a}$ . For this equation, $a=2$ , $b=5$ , $c=2$ . Then $\displaystyle \frac{-5 \pm \sqrt{25-16}}{4}$ . If the number inside the root has a $+$ sign, it has a real root. If the number is 0, then the quadratic equation has an equal root. If the number has $-$ sign, then it has imaginary roots. The quadratic equation $2x^2+5x+2=0$ has the number inside the root, $9$ , so it has 2 real roots.