So remember that area of a rectangle is a = bh. In this case, our sides are 2 and n - 3 (three less than unknown number) and our area is 22. Using our info, we can form the equation:
. From here we can solve for n.
Firstly, foil 2(n-3):
![22=2n-6](https://img.qammunity.org/2019/formulas/mathematics/college/mrcz01j0vka0yuuxiasmupgjb6zsjytqq0.png)
Next, add 6 on both sides of the equation:
![28=2n](https://img.qammunity.org/2019/formulas/mathematics/college/oenp3dqjhjo6p0uce1rsavpjvsb4lwq92m.png)
Next, divide both sides of the equation and your answer will be 14 = n. In context, the value of the unknown number is 14 in.