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):
Next, add 6 on both sides of the equation:
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.
The width is given. The area is given. That allows you to find out what the length is. From there you can find the unknown number which can be calculated.
Take a picture of the graph then re- upload the question with the same words from this one. without it i cannot solve the problem and the whole math equation relies on that graph which isn't here