How do you multiply 3x(5x^2-x+4)?

May 25, 2018

$15 {x}^{3} - 3 {x}^{2} + 12 x$

Explanation:

We need to distribute the $3 x$ to all terms in the parenthesis. We essentially have

$\textcolor{b l u e}{3 x} \left(5 {x}^{2}\right) - \textcolor{b l u e}{3 x} \left(x\right) + \textcolor{b l u e}{3 x} \left(4\right)$

Notice, the $3 x$ is being multiplied by all terms. We get

$\overline{\underline{| \textcolor{w h i t e}{\frac{2}{2}} 15 {x}^{3} - 3 {x}^{2} + 12 x \textcolor{w h i t e}{\frac{2}{2}} |}}$