Introduction to Algebra – Multiplication and Division
Please read Introduction to Algebra – Addition and Subtraction first
A Puzzle
What is the missing number?
The answer is 2, right? Because 2 × 4 = 8.
Well, in Algebra we don’t use blank boxes, we use a letter. So we might write:
which can simply be written like this “Put the number next to the letter to mean multiply”
You would say in English “four x equals eight”, meaning that 4 x’s make 8. And the answer would be written:
How to Solve
On the previous lesson we showed this neat stepbystep approach:
 Work out what to remove to get “x = …”
 Remove it by doing the opposite
 Do that to both sides
It still works, but you have to know that dividing is the opposite of multiplying. Have a look at this example:
We want to remove the “4“
To remove it, do the opposite, in this case divide both sides by 4:
Which is … Solved!
Just remember …
What you do to one side of the “=” you should also do to the other side! 
Another Puzzle
Solve this one: x / 3 = 5

x / 3 = 5 

x / 3 x 3= 5 x 3 

x = 15 
How would you solve this? x / 3 + 2 = 5
It might look hard, but not if you solve it in stages.
First let us get rid of the “+2“:

x/3 + 2 = 5 

x/3 + 2 2 = 5 2 

x/3 + 0 = 3 

x/3 = 3 
Now, get rid of the “/3“:

x/3 = 3 

x/3 ×3 = 3 ×3 

x = 9 
When you get more experienced:
When you get more experienced, you can solve it like this:

x/3 + 2 = 5 

x/3 = 3 

x = 9 
Have a Try Yourself
Now practice on this Simple Algebra Worksheet and then check your answers from the choices.
Try to use the steps we have shown you here, rather than just guessing!




