Answer:
x=3
y=-4
Step-by-step explanation:

What do you need help with
Answer:
-56
Step-by-step explanation:
You have a negative plus a positive which will give you a negative for the answer. Because you are adding a positive 28 to a negative 84 you get a negative 56.
The slope is 3
I am not that shure on the y intercept
From my research, the image below belongs to the question. From what is seen in the image, there are 2 arcs already drawn with respect to the new vertex. The third arc corresponds to the point where the line DM is made. This line is similar to line BC. So at the point where the second and third arcs would meet, it would be a point similar to a point on line AB.