Solve x2 + 14x = −24 by completing the square. What is the solution set of the equation? a. {−12, −2} b. {−7, 7} c. {−6, −4} d. {−5, 5}

Respuesta :

First, rearrange the equation so that only zero will be on the right side:

x^2 + 14x +24 = 0

Let the coefficients be:

a = 1

b = 14

c = 24

To complete the square, add (b/2)^2 to both sides of the equation:

(b/2)^2 = 49

x^2 + 14x + 49 + 24 = 49

x^2 + 14x + 49 = 25

(x+7)^2 = 25

Therefore, the solution set of the equation is {-12, -2}

The solution set of the quadratic equation x² + 14x = −24 is [-12, -2] option (a) is correct.

What is a quadratic equation?

Any equation of the form [tex]\rm ax^2+bx+c=0[/tex] where x is variable and a, b, and c are any real numbers where a ≠ 0 is called a quadratic equation.

As we know, the formula for the roots of the quadratic equation is given by:

[tex]\rm x = \dfrac{-b \pm\sqrt{b^2-4ac}}{2a}[/tex]

We have a quadratic equation:

x² + 14x = −24

It is required to solve the equation by completing the square.

First, arrange the quadratic equation

x² + 14x + 24 = 0

x² + 14x + 7² - 7² + 24 = 0

(x + 7)² -25 = 0

(x + 7)²  = 25

x + 7 = ±5

Taking positive sign:

x + 7 = 5

x = -2

Taking negative sign:

x + 7 = -5

x = -12

The solution set is [-12, -2]

Thus, the solution set of the quadratic equation x² + 14x = −24 is [-12, -2] option (a) is correct.

Learn more about quadratic equations here:

brainly.com/question/2263981

#SPJ5