Answer
The quadratic expression \( 3x^{2} - 6x - 9 \) can be factored as \( 3(x - 3)(x + 1) \). Solving the equation \( 3x^{2} - 6x - 9 = 0 \) gives the solutions \( x = 3 \) and \( x = -1 \).
Solution
It looks like you've provided the quadratic expression:
\[ 3x^{2} - 6x - 9 \]
Depending on what you're looking to do with this expression, here are a few common approaches:
### 1. **Factoring the Expression**
First, let's factor out the greatest common factor (GCF):
\[ 3x^{2} - 6x - 9 = 3(x^{2} - 2x - 3) \]
Now, factor the quadratic inside the parentheses:
We need two numbers that multiply to **-3** (the constant term) and add up to **-2** (the coefficient of the middle term).
The numbers **-3** and **+1** fit these requirements because:
- \(-3 \times 1 = -3\)
- \(-3 + 1 = -2\)
So, the factored form is:
\[ 3(x - 3)(x + 1) \]
### 2. **Solving the Equation \( 3x^{2} - 6x - 9 = 0 \)**
If you're looking to solve the quadratic equation, here's how you can do it:
**Step 1: Simplify the Equation**
Divide the entire equation by the GCF, which is 3:
\[ x^{2} - 2x - 3 = 0 \]
**Step 2: Factor the Simplified Equation**
As factored earlier:
\[ (x - 3)(x + 1) = 0 \]
**Step 3: Find the Solutions**
Set each factor equal to zero and solve for \( x \):
1. \( x - 3 = 0 \) ⟹ \( x = 3 \)
2. \( x + 1 = 0 \) ⟹ \( x = -1 \)
**Solutions:** \( x = 3 \) and \( x = -1 \)
### 3. **Using the Quadratic Formula**
Alternatively, you can use the quadratic formula to find the roots of the equation:
\[ ax^{2} + bx + c = 0 \]
For the equation \( 3x^{2} - 6x - 9 = 0 \):
- \( a = 3 \)
- \( b = -6 \)
- \( c = -9 \)
The quadratic formula is:
\[ x = \frac{-b \pm \sqrt{b^{2} - 4ac}}{2a} \]
Plugging in the values:
\[ x = \frac{6 \pm \sqrt{(-6)^{2} - 4(3)(-9)}}{2(3)} \]
\[ x = \frac{6 \pm \sqrt{36 + 108}}{6} \]
\[ x = \frac{6 \pm \sqrt{144}}{6} \]
\[ x = \frac{6 \pm 12}{6} \]
So, the solutions are:
1. \( x = \frac{6 + 12}{6} = \frac{18}{6} = 3 \)
2. \( x = \frac{6 - 12}{6} = \frac{-6}{6} = -1 \)
**Solutions:** \( x = 3 \) and \( x = -1 \)
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**Summary:**
- **Factored Form:** \( 3(x - 3)(x + 1) \)
- **Solutions to \( 3x^{2} - 6x - 9 = 0 \):** \( x = 3 \) and \( x = -1 \)
If you had a different operation or question in mind regarding this expression, please let me know!
Reviewed and approved by the UpStudy tutoring team
Explain
Simplify this solution