# What is the value of the discriminant for the quadratic equation 7r^2 -14r + 10 = 0?

Jun 7, 2018

$- 84$

#### Explanation:

For any quadratic of the form

$a {r}^{2} + b r + c$,

the discriminant is equal to

${b}^{2} - 4 a c$

In our quadratic, we know that $a = 7 , b = - 14$ and $c = 10$, so let's just plug these values into the value for the discriminant. We get

${\left(- 14\right)}^{2} - 4 \left(7\right) \left(10\right)$

which simplifies to

$196 - 4 \left(70\right)$

$\implies 196 - 280 = \textcolor{b l u e}{- 84}$

Therefore, the value of our discriminant is equal to

$\textcolor{b l u e}{- 84}$

Hope this helps!