The model represents [tex]$x^2 - 9x + 14$[/tex].

[tex]\[
\begin{array}{|c|c|c|c|c|c|c|c|c|}
\hline
+x^2 & -x & -x & -x & -x & -x & -x & -x \\
\hline
-x & + & + & + & + & + & + & + \\
\hline
-x & + & + & + & + & + & + & + \\
\hline
\end{array}
\][/tex]

Which is a factor of [tex]$x^2 - 9x + 14$[/tex]?

A. [tex]x-9[/tex]
B. [tex]x-2[/tex]
C. [tex]x+5[/tex]
D. [tex]x+7[/tex]



Answer :

To determine which one is a factor of the quadratic equation [tex]\(x^2 - 9x + 14\)[/tex], we should factorize the quadratic polynomial. Let's go through the steps of factorization carefully:

1. Given Polynomial:
[tex]\[ x^2 - 9x + 14 \][/tex]

2. Identify the Coefficients:
Here, the coefficient of [tex]\(x^2\)[/tex] is 1, the coefficient of [tex]\(x\)[/tex] is -9, and the constant term is 14.

3. Factorization Method:
We need to express the quadratic polynomial in the form:
[tex]\[ x^2 - 9x + 14 = (x - a)(x - b) \][/tex]
where [tex]\(a\)[/tex] and [tex]\(b\)[/tex] are numbers that need to be determined.

4. Find [tex]\(a\)[/tex] and [tex]\(b\)[/tex]:
[tex]\(a\)[/tex] and [tex]\(b\)[/tex] should satisfy two conditions:
- The product [tex]\(a \cdot b = 14\)[/tex]
- The sum [tex]\(a + b = 9\)[/tex]

5. Determine the Pair (a, b):
We need to find pairs of numbers that multiply to 14 and add up to 9.
[tex]\[ \begin{array}{ccc} 7 \cdot 2 &= 14 & \quad 7 + 2 = 9 \\ -7 \cdot (-2) &= 14 & \quad -7 + (-2) = -9 \quad (\text{wrong sum}) \\ -2 \cdot (-7) &= 14 & \quad -2 + (-7) = -9 \quad (\text{wrong sum}) \\ \end{array} \][/tex]

The correct pair is [tex]\(7\)[/tex] and [tex]\(2\)[/tex].

6. Write the Factored Form:
Substituting [tex]\(a\)[/tex] and [tex]\(b\)[/tex] into our factor form:
[tex]\[ x^2 - 9x + 14 = (x - 7)(x - 2) \][/tex]

Therefore, the factors are [tex]\((x - 7)\)[/tex] and [tex]\((x - 2)\)[/tex].

7. Verify Factors:

- Option [tex]\(x - 9\)[/tex] does not satisfy the factorization.
- Option [tex]\(x - 2\)[/tex] is a factor.
- Option [tex]\(x + 5\)[/tex] does not match the factorization.
- Option [tex]\(x + 7\)[/tex] does not match the factorization (it should be [tex]\(x - 7\)[/tex]).

Conclusion:
The factor of [tex]\(x^2 - 9x + 14\)[/tex] from the given options is:

[tex]\[ x - 2 \][/tex]