Question

Find the zeros of y= x - 4x - 9 by completing the square.

O A. *= 2: 113
O B. x= 3+ /13
O c. *= +3
O D. x=-21,13

Answer 1

The zeros for the given equation are A.
`x = {2 \pm √(13)}.`

Explanation:

Step 1:

To solve for x in a polynomial equation, we use the formula

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

Here a is the coefficient of
`x^(2)`, b is the coefficient of
`x` and c is the coefficient of the constant term.

In the given equation,
`a = 1, b = -4, c = -9`.

Step 2:

Substituting the values of a, b, and c in the equation, we get

`x=\frac{-b \pm \sqrt{b^(2)-4 a c}}{2 a} =\frac{-(-4) \pm \sqrt{(-4)^(2)-4 (1)(-9)}}{2 (1)} = (4 \pm √((16+36))/(2 ).`

`(4 \pm √((16+36))/(2 ) = (4 \pm √((52))/(2 ) = (4 \pm2 √((13))/(2 )= {2 \pm √(13)}.`

So the answer is option A.
`x = {2 \pm √(13)}.`