# How do u do the problem 3x·(7·x) simplified?

Mar 7, 2018

$21 {x}^{2}$

#### Explanation:

You simply multiply $3 x$ to all what is inside the parentheses. Luckily, you have here just $7 x$.

Another example,

$2 x \cdot \left(5 x + 4 x\right) = 10 {x}^{2} + 8 {x}^{2} = 18 {x}^{2}$

Mar 7, 2018

$21 {x}^{2}$

#### Explanation:

I am understanding the expression $3 x \setminus \times 7 x$. The steps below are for simplifying that expression.

Multiply the coefficients together - meaning 3 and 7 - and you should get 21.

Multiply $x$ by $x$, and it should be ${x}^{2}$.

Put 21 and ${x}^{2}$ together to get $21 {x}^{2}$.