Brian is solving the equation x^2-3/4x=5. what value must be added to both sides of the equation to make the left side a perfect-square trinomial?

Answer asap. you begin with 1/2 scoop of ice cream. since you're hungry, you ask the vendor for 2/7 more scoops of ice cream. then, you eat 5/8 scoops. how many scoops of ice cream are left on your cone? i will mark brainliest for first correct answer.