Question

Item 8 factor −5 out of −10a−25.

Answer 1

To factor a number out of an expression means to divide each term of the expression by that number.

So, if you want to factor
`a` from the expression
`x+y+z`, you'll write it as

`a\left((x)/(a)+(y)/(a)+(z)/(a)\right)`

So, in your case, when you divide both terms by -5 you get

`-10a / (-5) = 2a,\quad -25/ (-5) = 5`

So, the expression becomes

`-10a-25 = -5(2a+5)`