Question

Given the Question below which of the following shows the quadratic formula correctly applied?

Answer 1

D.

`x = \frac{ - ( - 9 )\pm \sqrt{ {( - 9)}^(2) - 4(2)(4)} }{2(2)}`

Step-by-step explanation

The given equation is

`2 {x}^(2) - 9x + 4 = 0`

When we compare this to:

`a{x}^(2) + bx + c = 0`

we have a=2, b=-9, and c=4.

The quadratic formula is given by,

`x = \frac{ - b \pm \sqrt{ {b}^(2) - 4ac} }{2a}`

We substitute the values into the formula to get,

`x = \frac{ - ( - 9 )\pm \sqrt{ {( - 9)}^(2) - 4(2)(4)} }{2(2)}`

The correct choice is D