Which is a solution to 2x + 1 = 21?

x = 10 is your answer

- Explain -

Step 1: subtract 1 from both sides (subtraction of equality)

which will give us:

2x = 21 - 1

which equals to

2x = 20

Step 2: Divide both sides by 2

which is

2x/2 = 20/2

2/2 = 1 and 20/2 = 10

Therefore the answer is x = 10