In this activity, we will be finding the formula that matches the results in the given table.

Example

Find the formula that matches the results in this table.

Which formula will match the results?

1.  b = 2a

2.  b = 3a - 1

3.  b = 2a + 1

Answer

We test out each formula in turn.

b = 2a doesn't work for any of the rows.

b = 3a - 1 works for when a = 2 and b = 5 , but not for the other rows.

b = 2a + 1 works for all the rows, as you have to double the a number and add 1 to get the b number.

So, the answer is b = 2a + 1

Shall we have a go at this now in the following questions?