Find the Discriminant 2x^2-x+9=0

$2 x^{2} - x + 9 = 0$

Step 1

The discriminant of a quadratic is the expression inside the radical of the quadratic formula.

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

Step 2

Substitute in the values of $a$ , $b$ , and $c$ .

${(- 1)}^{2} - 4 (2 \cdot 9)$

Step 3

Evaluate the result to find the discriminant.

Simplify each term.

Raise $- 1$ to the power of $2$ .

$1 - 4 (2 \cdot 9)$

Multiply $- 4 (2 \cdot 9)$ .

Multiply $2$ by $9$ .

$1 - 4 \cdot 18$

Multiply $- 4$ by $18$ .

$1 - 72$

Subtract $72$ from $1$ .

$- 71$