NotYourStudent
NotYourStudent NotYourStudent
  • 11-03-2019
  • Mathematics
contestada

PLEASE HELP
Solve the equation, x2 - 2x - 8 = 0 by completing the square .

a. x = 4 or x = -2

b. x = 4 or x = 2

c. x = -4 or x = -2

d. x = -4 or x = 2

Respuesta :

MrsStrong
MrsStrong MrsStrong
  • 14-03-2019

Answer:

A

Step-by-step explanation:

Completing the square requires a quadratic in [tex]ax^2+bx=c[/tex] form. Once in this form, calculate [tex](\frac{b}{2})^2[/tex].

Here x2 - 2x - 8 = 0 converts to x2 - 2x = 8. So b = -2.

[tex](\frac{b}{2})^2=(\frac{-2}{2})^2=1[/tex]

Add 1 to both sides.

x2 - 2x + 1 = 8 + 1

(x -1)^2 = 9

Square root both sides.

x-1 = 3                        x - 1 = -3

x = 4                           x = -2

This is the solution.

Answer Link

Otras preguntas

which statement about artist from Italy and Northern Europe is true
What is the simplest form of 8/28?
Which science tool colud be used to reflect light
What is the difference between a criminal case and a civil case?
pronoun for A ti _____ gustan las plantas
Based on the definition given, which sentence most correctly uses the word describe?[describe: to explain or portray an impression] a. the describe is in that
what grade is 85 out of 120?
which of the following statements is true of Mycenaean civilization but not of minoan civilization? It achieves prosperity It controlled the island of Crete It
With only one wish, Gwen gazed into the orb she wanted to see into her future.
Locate the adverb phrase and the word or phrase it modifies. The noise is coming from the hallway.