How much assembly do you already know? Its really probably not all that hard to do. You need to declare storage for four variables, a, b, c and d. First calcaulate c^2 (which is just c * c), and d^2 (d * d). store that result away somewhere. Then calculate a+b. Finally divide the result of a+b by the denominator previously calculated.
Will I write this for you? No. Its your homework, not mine.