Answer:
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The equation should look something like this.

Be careful with your use between cubing and multiplying; Cubing is multiplying the number by itself multiple times, while multiplying is like repeated adding, yet much easier.
In this case, if it says triple, I highly recommend multiplying by 3, which is what I did, it only looks different because it is in parentheses.
What have we learned?
<h3>We learned how to write algebraic equations, and some further information on multiplying.</h3>