Answer:
1. y = 1/4 and y = 1/4x+2
2. y - 1 = -x (x + 7) and y = -x and x + y = 3
-------
4. y = 3 and x = 6
5. y = 1/2x + 2 and y + 1 = -2x
6. Slope of AB = 2/3
Slope of BC = -3/2
AB is perpendicular to BC because 2/3(-2/3) = -1
ABC is a right triangle because it contains a right angle
