To find the perfect square needed, you take the "middle" value and half it, then square it. so in this case, take -6, half it into 3, and square it to get 9. you'll be adding 9 to both sides
The awenser of the problem is A
Answer:
Slope of the line DV = -1
Step-by-step explanation:
Let point D (-5, 1) be 
Let point V (-1, -3) be 

Plug in the appropriate values,

slope equals -1