Step by step
The question
Question: are 6(x + 3) − 4 and 6x + 14 equivalent?
Equivalent means: the two are equal, whatever number the letter is.
First we simplify the first one: 6(x + 3) − 4.
We write it shorter, with the same value.
1 Open the brackets
The 6 in front of the bracket multiplies every part inside.
So we write 6 times each part.
6 times x is 6x.
6 times 3 is 18.
2 Group like terms
Terms are the parts between the + and − signs.
Like terms are the same kind: same letters, same powers.
Plain numbers go together.
Each colour is one kind.
18 − 4 is 14.
So the expression is 6x + 14.
3 Compare
Now both are 6x + 14.
The same terms.
So yes: they are equivalent.
4 Check
Let's check with a number: x = 2.
The first gives 26.
The second gives 26.
The same.
So the answer is right!
Let's look back.
First: open the brackets.
Then: group like terms.
Then: compare.
Last: check.