Question

Six times the sum of a number and nine is 18.find the number?

Answer 1

The given problem says:

Six times the sum of a number and nine is 18.

So, let's set "n" as the unknown number.

Then, the sum of a number and nine is:

`n+9`

And six times this sum, is:

`6(n+9)`

The result of the sum is 18, so:

`6(n+9)=18`

Let's solve for n:

`\begin{gathered} \text{ Divide both sides by 6:} \\ (6(n+9))/(6)=(18)/(6) \\ \\ n+9=3 \\ \text{ Subtract 9 from both sides} \\ n+9-9=3-9 \\ n=-6 \end{gathered}`

The number is -6.