Solve [tex](x-4)^2=5[/tex].

A. [tex]x=4 \pm \sqrt{5}[/tex]
B. [tex]x=9[/tex] and [tex]x=-1[/tex]
C. [tex]x=5 \pm \sqrt{4}[/tex]
D. [tex]x=-4 \pm \sqrt{5}[/tex]



Answer :

Let's solve the equation [tex]\((x - 4)^2 = 5\)[/tex].

### Step-by-Step Solution:

1. Start with the given equation:
[tex]\[ (x - 4)^2 = 5. \][/tex]

2. Take the square root of both sides to remove the squared term:
[tex]\[ \sqrt{(x - 4)^2} = \sqrt{5}. \][/tex]
Recall that taking the square root of both sides gives us two separate equations because of the property [tex]\(\sqrt{a^2} = \pm a\)[/tex].

3. Apply the [tex]\(\pm\)[/tex] (plus and minus) sign:
[tex]\[ x - 4 = \pm \sqrt{5}. \][/tex]

4. Separate this into two individual equations:
[tex]\[ x - 4 = \sqrt{5}, \][/tex]
and
[tex]\[ x - 4 = -\sqrt{5}. \][/tex]

5. Solve each equation for [tex]\(x\)[/tex]:

- For the first equation:
[tex]\[ x - 4 = \sqrt{5} \implies x = 4 + \sqrt{5}. \][/tex]
- For the second equation:
[tex]\[ x - 4 = -\sqrt{5} \implies x = 4 - \sqrt{5}. \][/tex]

6. Combine the solutions:
Thus, we get two solutions for [tex]\(x\)[/tex]:
[tex]\[ x = 4 + \sqrt{5} \quad \text{and} \quad x = 4 - \sqrt{5}. \][/tex]

### Final Answer:
By comparing these solutions with the given choices:

- A. [tex]\(x = 4 \pm \sqrt{5}\)[/tex]
- B. [tex]\(x = 9\)[/tex] and [tex]\(x = -1\)[/tex]
- C. [tex]\(x = 5 \pm \sqrt{4}\)[/tex]
- D. [tex]\(x = -4 \pm \sqrt{5}\)[/tex]

The correct answer is:
[tex]\[ \boxed{A. \ x = 4 \pm \sqrt{5}} \][/tex]