Solve Two-Stage Equations with Brackets

When we solve algebraic equations, our aim is to end up with one letter on one side of the equals sign and one number on the other.  This is the solution.

 

We do this by using inverse operations to undo things that get in the way, but remember that we must do the same thing to both sides.

 

Example

Solve  4(2b + 1) = 3(8 + b)

 

Answer

Multiply out the brackets:

8b + 4 = 24 + 3b

 

Subtract 4 from both sides:

8b + 4 - 4 = 24 + 3b - 4

 

Simplify:

8b = 20 + 3b

 

Subtract 3b from both sides:

8b - 3b = 20 + 3b - 3b

 

Simplify:

5b = 20

 

Divide both sides by 5:

5b ÷ 5 = 20 ÷ 5

 

Simplify:

b = 4

 

Want a bit more help with this before you begin? Why not watch this short video?