How do you factor #5a - 20 #?

2 Answers
May 15, 2016

Answer:

#5(a-4)#

Explanation:

We begin with #5a-20#. The first thing I noticed with this problem is that both #5# and #20# are divisible by #5#. That means that we can factor out a #5# from both components, which leaves us with #5(a-4)#.

There, that's it. #5(a-4)# cannot be factored any further.

May 15, 2016

Answer:

#5(a-4)#

Explanation:

To factor this expression, tell yourself
"I need a number (or variable) that 'go into' both 5a and -20.
Well, 5 is a factor of 5 and -20.
So 5 go into 5a (1a times).
That sounds confusing, but remember, 5 go into 5 one time, but in algebra, you don't normally write the number 1 in coefficient, so it's just 'a'. 5 can't go into 'a' because a is just a single variable.
5 can go into 20, 4 times.
So now our final answer will be 5(a-4).
Hopefully this make sense!