7).
In the graph 7
The two coordinates are (-1,-1) and (1,3)
The slope of a line is expresses as :

Answer slope of grap 7 is 2.
8)
In the graph 8
The coordinates are (-2,4) and (2,0)
The slope will express as :

Slope of graph 8 is (-1).
Answer :
(7) slope = 2
(8) slope = -1