Simplify 4a + 3b − a + 5b.

Step by step

The question

Question: simplify 4a + 3b − a + 5b.

Simplify means: write it shorter, with the same value.

1 Group like terms

Terms are the parts between the + and − signs.

Like terms are the same kind: same letters, same powers.

All the a terms go together.

Each colour is one kind.

We move like terms next to each other.

Each term takes its sign with it.

a alone means 1a.

4a − a is 3a.

It is like 4 apples take away 1 apple: that is 3 apples.

3b + 5b is 8b.

So the expression is 3a + 8b.

2 Check

Let's check.

We pick a small number for each letter: a = 2, b = 3.

Any number works, and a small one keeps the sums easy.

We put it into the question.

Now into our answer.

Both give 30.

Same value, so 3a + 8b is right!

Let's look back.

First: group like terms.

Last: check.