Identifying Quadratic Functions in Factored Form

Match each quadratic function given in factored form with its equivalent standard form listed on the left.

A. [tex]\(f(x) = x^2 - 11x - 12\)[/tex]
B. [tex]\(f(x) = x^2 - 4x - 12\)[/tex]
C. [tex]\(f(x) = x^2 + x - 12\)[/tex]
D. [tex]\(f(x) = x^2 - x - 12\)[/tex]

1. [tex]\(f(x) = (x+2)(x-6)\)[/tex]
2. [tex]\(f(x) = (x-4)(x+3)\)[/tex]
3. [tex]\(f(x) = (x-12)(x+1)\)[/tex]
4. [tex]\(f(x) = (x-3)(x+4)\)[/tex]



Answer :

To match each quadratic function given in factored form with its equivalent standard form, we need to expand each factored form and compare it with the standard forms provided. Let's proceed step by step.

### 1. Expanding Factored Forms

a. [tex]\( (x + 2)(x - 6) \)[/tex]

[tex]\[ (x + 2)(x - 6) = x(x - 6) + 2(x - 6) = x^2 - 6x + 2x - 12 = x^2 - 4x - 12 \][/tex]

b. [tex]\( (x - 4)(x + 3) \)[/tex]

[tex]\[ (x - 4)(x + 3) = x(x + 3) - 4(x + 3) = x^2 + 3x - 4x - 12 = x^2 - x - 12 \][/tex]

c. [tex]\( (x - 12)(x + 1) \)[/tex]

[tex]\[ (x - 12)(x + 1) = x(x + 1) - 12(x + 1) = x^2 + x - 12x - 12 = x^2 - 11x - 12 \][/tex]

d. [tex]\( (x - 3)(x + 4) \)[/tex]

[tex]\[ (x - 3)(x + 4) = x(x + 4) - 3(x + 4) = x^2 + 4x - 3x - 12 = x^2 + x - 12 \][/tex]

### 2. Matching Standard Forms

Standard Forms:

A. [tex]\( x^2 - 11x - 12 \)[/tex]
B. [tex]\( x^2 - 4x - 12 \)[/tex]
C. [tex]\( x^2 + x - 12 \)[/tex]
D. [tex]\( x^2 - x - 12 \)[/tex]

Factored Forms and Expanded Results:

1. [tex]\( (x + 2)(x - 6) = x^2 - 4x - 12 \)[/tex]
2. [tex]\( (x - 4)(x + 3) = x^2 - x - 12 \)[/tex]
3. [tex]\( (x - 12)(x + 1) = x^2 - 11x - 12 \)[/tex]
4. [tex]\( (x - 3)(x + 4) = x^2 + x - 12 \)[/tex]

### 3. Final Matching:

[tex]\[ \begin{array}{llll} A & \rightarrow & (x - 12)(x + 1) & : x^2 - 11x - 12 \\ B & \rightarrow & (x + 2)(x - 6) & : x^2 - 4x - 12 \\ C & \rightarrow & (x - 3)(x + 4) & : x^2 + x - 12 \\ D & \rightarrow & (x - 4)(x + 3) & : x^2 - x - 12 \\ \end{array} \][/tex]

So, the matches are:

A. [tex]\( f(x) = x^2 - 11x - 12 \)[/tex] matches with [tex]\( (x - 12)(x + 1) \)[/tex]
B. [tex]\( f(x) = x^2 - 4x - 12 \)[/tex] matches with [tex]\( (x + 2)(x - 6) \)[/tex]
C. [tex]\( f(x) = x^2 + x - 12 \)[/tex] matches with [tex]\( (x - 3)(x + 4) \)[/tex]
D. [tex]\( f(x) = x^2 - x - 12 \)[/tex] matches with [tex]\( (x - 4)(x + 3) \)[/tex]