f) $d(d-15)=0$
\(\boxed{Final Answer: The solutions for the equation d(d-15)=0 are d = 0 and d = 15.}\)
Step 1 :Solve the quadratic equation \(d(d-15)=0\) for the variable d.
Step 2 :\(d = d\)
Step 3 :\(equation = d(d - 15)\)
Step 4 :\(solutions = [0, 15]\)
Step 5 :\(\boxed{Final Answer: The solutions for the equation d(d-15)=0 are d = 0 and d = 15.}\)