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Day 3 : Finding the unknown variable value with the Balance MethodDescription: Basic balancing of equal expressions
Objective: The purpose of this exercise is to make two expressions equal to each other by finding the correct input value for the variable in the expressions. This is done using the balance method which assumes that the two expressions are equal or balanced and then makes equal changes to both sides until the correct choice of variable is more obvious
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08.004 Equations.Multiplied

Evaluate a where : 6a = 24

In this question we are told that 6 multiplied by some unknown value 'a'  gives the result 24.

Clearly the answer is 4 because 6 times by 4 gives the result 24.

However, for more difficult questions we solve this using the balance method

The balance method means that => Whatever we do to the left hand side  we do the same to the right hand side.

On the left hand side we have 6 multiplied by a.  To get 'a' on its own, we UNDO this.  The opposite of multiplying is dividing.

So 6 times by 'a'  divided by 6 gets us back to where we started.

i.e. 'a'.

      6a = 24

divide both sides by 6.

   a = 4

 

Check your answer.

   6 x 4 = 24

Correct.

And that's it.