Welcome to Westonci.ca, where you can find answers to all your questions from a community of experienced professionals. Our platform provides a seamless experience for finding precise answers from a network of experienced professionals. Experience the convenience of finding accurate answers to your questions from knowledgeable experts on our platform.

Which of the following are solutions to the equation below? Check all that apply.

4x^2 + 20x + 25 = 49

A. x = -1
B. x = 6
C. x = [tex]\(\frac{\sqrt{7}-5}{2}\)[/tex]
D. x = [tex]\(\frac{-\sqrt{7}-5}{2}\)[/tex]
E. x = 1
F. x = 6


Sagot :

To determine which values are solutions to the given equation:
[tex]\[ 4x^2 + 20x + 25 = 49 \][/tex]

We need to follow these steps:

1. Simplify the equation to standard form by subtracting 49 from both sides:
[tex]\[ 4x^2 + 20x + 25 - 49 = 0 \][/tex]
[tex]\[ 4x^2 + 20x - 24 = 0 \][/tex]

2. Solve the quadratic equation:
[tex]\[ 4x^2 + 20x - 24 = 0 \][/tex]

To find the solutions, we can use the quadratic formula:
[tex]\[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \][/tex]
In our equation, [tex]\( a = 4 \)[/tex], [tex]\( b = 20 \)[/tex], and [tex]\( c = -24 \)[/tex].

Calculating the discriminant:
[tex]\[ \Delta = b^2 - 4ac \][/tex]
[tex]\[ \Delta = 20^2 - 4(4)(-24) \][/tex]
[tex]\[ \Delta = 400 + 384 \][/tex]
[tex]\[ \Delta = 784 \][/tex]

Solving for [tex]\( x \)[/tex]:
[tex]\[ x = \frac{-20 \pm \sqrt{784}}{2 \cdot 4} \][/tex]
[tex]\[ x = \frac{-20 \pm 28}{8} \][/tex]

This gives two possible solutions:
[tex]\[ x = \frac{-20 + 28}{8} = \frac{8}{8} = 1 \][/tex]
[tex]\[ x = \frac{-20 - 28}{8} = \frac{-48}{8} = -6 \][/tex]

The solutions to the equation [tex]\( 4x^2 + 20x + 25 = 49 \)[/tex] are [tex]\( x = 1 \)[/tex] and [tex]\( x = -6 \)[/tex].

Now, let's check the given options:

A. [tex]\( x = -1 \)[/tex]
- Substitute [tex]\( x = -1 \)[/tex]:
[tex]\[ 4(-1)^2 + 20(-1) + 25 = 4 - 20 + 25 = 9 \][/tex]
This does not satisfy the equation [tex]\( 4x^2 + 20x + 25 = 49 \)[/tex].
- Not a solution.

B. [tex]\( x = 6 \)[/tex]
- Substitute [tex]\( x = 6 \)[/tex]:
[tex]\[ 4(6)^2 + 20(6) + 25 = 144 + 120 + 25 = 289 \][/tex]
This does not satisfy the equation [tex]\( 4x^2 + 20x + 25 = 49 \)[/tex].
- Not a solution.

C. [tex]\( x = \frac{\sqrt{7}-5}{2} \)[/tex]
- Substitute [tex]\( x = \frac{\sqrt{7}-5}{2} \)[/tex]:
[tex]\[ \text{This value does not satisfy the simplified quadratic equation.} \][/tex]
- Not a solution.

D. [tex]\( x = \frac{-\sqrt{7}-5}{2} \)[/tex]
- Substitute [tex]\( x = \frac{-\sqrt{7}-5}{2} \)[/tex]:
[tex]\[ \text{This value does not satisfy the simplified quadratic equation.} \][/tex]
- Not a solution.

E. [tex]\( x = 1 \)[/tex]
- Substitute [tex]\( x = 1 \)[/tex]:
[tex]\[ 4(1)^2 + 20(1) + 25 = 4 + 20 + 25 = 49 \][/tex]
This does satisfy the equation.
- This is a solution.

F. [tex]\( x = 6 \)[/tex]
- Substitute [tex]\( x = 6 \)[/tex]:
[tex]\[ 4(6)^2 + 20(6) + 25 = 289 \][/tex]
This does not satisfy the equation.
- Not a solution.

Therefore, the solutions that apply are:

- [tex]\( x = 1 \)[/tex] (Option E)