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Factorise: 3x ^(2) - 4x -4...

Factorise:
`3x ^(2) - 4x -4`

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To factorise the quadratic expression \(3x^2 - 4x - 4\), we can follow these steps: ### Step 1: Identify the coefficients The quadratic expression is in the form \(ax^2 + bx + c\), where: - \(a = 3\) - \(b = -4\) - \(c = -4\) ### Step 2: Calculate the product \(ac\) We need to calculate the product of \(a\) and \(c\): \[ ac = 3 \times (-4) = -12 \] ### Step 3: Find two numbers that multiply to \(ac\) and add to \(b\) We need to find two numbers that multiply to \(-12\) (the value of \(ac\)) and add to \(-4\) (the value of \(b\)). The two numbers that satisfy this condition are \(-6\) and \(2\): \[ -6 \times 2 = -12 \quad \text{and} \quad -6 + 2 = -4 \] ### Step 4: Rewrite the middle term We can rewrite the quadratic expression by splitting the middle term using the two numbers found: \[ 3x^2 - 6x + 2x - 4 \] ### Step 5: Group the terms Now, we will group the terms: \[ (3x^2 - 6x) + (2x - 4) \] ### Step 6: Factor out the common factors from each group From the first group \(3x^2 - 6x\), we can factor out \(3x\): \[ 3x(x - 2) \] From the second group \(2x - 4\), we can factor out \(2\): \[ 2(x - 2) \] ### Step 7: Combine the factored groups Now we can combine the factored groups: \[ 3x(x - 2) + 2(x - 2) \] We can factor out the common binomial \((x - 2)\): \[ (x - 2)(3x + 2) \] ### Final Result Thus, the factorised form of the expression \(3x^2 - 4x - 4\) is: \[ \boxed{(x - 2)(3x + 2)} \] ---
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