Question 1: Part A
To factor the equation \(3x^2 + 13x + 12 = 0\) using factoring by grouping, we first multiply \(A\) (the coefficient of \(x^2\), which is 3) and \(C\) (the constant term, which is 12).
Now, \(A \cdot C = 3 \cdot 12 = 36\). We need to find two numbers that multiply to 36 and add up to 13. The appropriate pairs are 9 and 4, so we can rewrite the equation:
\[ 3x^2 + 9x + 4x + 12 = 0 \]
Thus, the correct option is:
3x² + 9x + 4x + 12 = 0
Question 2: Part B
Now, after rewriting the equation as \(3x^2 + 9x + 4x + 12 = 0\), we can group the terms:
\[ (3x^2 + 9x) + (4x + 12) = 0 \]
Factoring each group gives:
\[ 3x(x + 3) + 4(x + 3) = 0 \]
Now factor out the common term \((x + 3)\):
\[ (3x + 4)(x + 3) = 0 \]
So, the correct option is:
(3x + 4)(x + 3) = 0
Question 3: Part C
To find the solutions, we set each factor to zero:
- \(3x + 4 = 0\) implies \(3x = -4\) or \(x = -\frac{4}{3}\)
- \(x + 3 = 0\) implies \(x = -3\)
The solutions are:
x = -\frac{4}{3} and x = -3
So the corresponding option is:
x = -\frac{4}{3} and x = -3.