If u use a calculator the answer would be zero

Here is the basis equation.

Let us use the AC method. Multiple the A and C values, or 3 and -5. This is -15. So now ask yourself... what multiplies to -15 but adds to -2. that would be, -5 and 3. So now reconstruct your equation ...

The larger number will go first (3>-5)
Now you can factor each group.

Because what is now in the parentheses are qualm and they are being added, you can now make the coeffecients a group

If you are solving for p, set equal to zero and then the answers are -1 and (5/3). If you are just factoring, then that is your answer.
to plot start at the orgin (0,0) and move 1/3 right and 3 down.
In order to find the firms demand for labor you havr to solve the profit maximization problem that the firm faces, the problem can be dexcribed mathematically in your example with the following formulas,

Solving this problem will result to a function that relates the amount of labour (L) with wage(w)