How do you factor 10a^2+40a?

Jun 11, 2018

$10 a \left(a + 4\right)$

Explanation:

Expression $= 10 {a}^{2} + 40 a$

First notice that 10 is a factor of both terms.

$\therefore$ Expression $= 10 \left({a}^{2} + 4 a\right)$

Now notice that $a$ is a factor of both terms in parentheses

$\therefore$ Expression $= 10 a \left(a + 4\right)$
No further factorisation of the expression is possible.

Jun 11, 2018

$10 a \left(a + 4\right)$
When factoring, you have to take out the variable(s) (in this case $a$) and number(s) $\left(10\right)$ that can be divided out of the equation, they must be divided by each part of the expression.
$10 a$ can be divided out of the expression only because it can be divided from both.