I cannot figure out how to start coding a problem like this. ( basically i cant figure out how to create the formula )

A fence is around a field in the shape shown below and consists of the rectangle length (L) and width (W), and a right triangle. Both sides of the right triangle have a length of D. Suppose the enclosed area (A) and the width (W) are both known. A. Write an expression that expresses D in terms of W ii. Write an expression for the area of the shape in terms of W, L and D iii. Substitute your expression from i) into ii) iv. Solve iii) for L b. Write a Matlab function to return the length, L and the perimeter of the field, P. There are two inputs (A and W) and two outputs (L and P) for this function. You should use the equation you derived in part a) to calculate L. The perimeter is the sum of all the sides. You can calculate D by using the expression you came up with in part i.