Answer: k=9/4
Step-by-step explanation: We can do this by finding a number that adds up to 3 when multiplied by 2. The best way to do this is to use ((b^2)/4) which can usually find you the number for a perfect square based on b, which we have. So, 3^2 / 4 =9/4, meaning k=9/4. We can check:
>x^2 +3x +9/4
> (x+3/2)(x+3/2)
Perfect square.
