Find expert answers and community insights on IDNLearn.com. Discover reliable and timely information on any topic from our network of experienced professionals.

Select the correct answer.

What are the solutions to this quadratic equation?
[tex]\[ x^2 + 13 = 8x + 37 \][/tex]

A. [tex]\( x = -4 \pm 4\sqrt{10} \)[/tex]
B. [tex]\( x = 4 \pm \sqrt{10} \)[/tex]
C. [tex]\( x = -2 \pm 4\sqrt{10} \)[/tex]
D. [tex]\( x = 4 \pm 2\sqrt{10} \)[/tex]


Sagot :

Certainly! Let's solve the quadratic equation step-by-step:

1. Given Equation:
[tex]\[ x^2 + 13 = 8x + 37 \][/tex]

2. Rearrange into Standard Quadratic Form:
Move all terms to one side to get:
[tex]\[ x^2 - 8x + 13 - 37 = 0 \][/tex]
Simplify the constants:
[tex]\[ x^2 - 8x - 24 = 0 \][/tex]

3. Identify Coefficients:
The quadratic equation is now in the form [tex]\( ax^2 + bx + c = 0 \)[/tex]:
[tex]\[ a = 1, \quad b = -8, \quad c = -24 \][/tex]

4. Calculate the Discriminant:
The discriminant [tex]\(\Delta\)[/tex] is given by:
[tex]\[ \Delta = b^2 - 4ac \][/tex]
Substitute the values of [tex]\(a\)[/tex], [tex]\(b\)[/tex], and [tex]\(c\)[/tex]:
[tex]\[ \Delta = (-8)^2 - 4(1)(-24) \][/tex]
Calculate:
[tex]\[ \Delta = 64 + 96 = 160 \][/tex]

5. Check the Discriminant:
Since the discriminant is positive ([tex]\( \Delta > 0 \)[/tex]), there are two distinct real solutions.

6. Quadratic Formula:
The solutions [tex]\(x\)[/tex] are given by:
[tex]\[ x = \frac{-b \pm \sqrt{\Delta}}{2a} \][/tex]
Substitute [tex]\(a = 1\)[/tex], [tex]\(b = -8\)[/tex], and [tex]\(\Delta = 160\)[/tex]:
[tex]\[ x = \frac{-(-8) \pm \sqrt{160}}{2 \cdot 1} \][/tex]
Simplify:
[tex]\[ x = \frac{8 \pm \sqrt{160}}{2} \][/tex]

7. Simplify Further:
Notice that [tex]\(\sqrt{160}\)[/tex] can be simplified:
[tex]\[ \sqrt{160} = \sqrt{16 \times 10} = 4\sqrt{10} \][/tex]
So the expression for [tex]\(x\)[/tex] becomes:
[tex]\[ x = \frac{8 \pm 4\sqrt{10}}{2} \][/tex]
Divide through by 2:
[tex]\[ x = 4 \pm 2\sqrt{10} \][/tex]

Thus, the solutions to the quadratic equation are:
[tex]\[ x = 4 \pm 2\sqrt{10} \][/tex]

Therefore, the correct answer is:
D. [tex]\(x = 4 \pm 2\sqrt{10}\)[/tex]