The correct linear factors of the polynomial

20
𝑥
3

96
𝑥
2

144
𝑥
20x
3
−96x
2
−144x are:

4x(5x + 6)(x - 6).

1 answer

To factor the polynomial \(20x^3 - 96x^2 - 144x\), you can start by factoring out the greatest common factor (GCF) from all the terms.

The GCF of the coefficients \(20\), \(-96\), and \(-144\) is \(4\), and all terms have at least one factor of \(x\). Thus, we can factor out \(4x\):

\[ 20x^3 - 96x^2 - 144x = 4x(5x^2 - 24x - 36) \]

Next, we need to factor the quadratic \(5x^2 - 24x - 36\). We can look for two numbers that multiply to \(5 \times -36 = -180\) and add to \(-24\). The numbers that meet these criteria are \(-30\) and \(6\).

Now we can split the middle term and factor by grouping:

\[ 5x^2 - 30x + 6x - 36 \]

Grouping gives us:

\[ (5x^2 - 30x) + (6x - 36) \]

Factoring each group results in:

\[ 5x(x - 6) + 6(x - 6) \]

Now we can factor out the common binomial factor \(x - 6\):

\[ (5x + 6)(x - 6) \]

Putting it all together, we have:

\[ 20x^3 - 96x^2 - 144x = 4x(5x + 6)(x - 6) \]

Thus, the correct linear factors of the polynomial \(20x^3 - 96x^2 - 144x\) are:

\[ \boxed{4x(5x + 6)(x - 6)} \]