A) Y1-Y2/X1-X2
9-4/8-(-2) = 5/10= 1/2
b) 1/2x+b=y <-- plug in a point
1/2(-2)+b=4 <--plugged in (-2,4)
-1+b=4 <-- simplify/solve
b=5
c) 1/2x+5=y
250 is one inch
100 is 0.4 inch
10 is 0.04 inch
21
that is the answer
learn your times table.
It is the point where the line on the graph crosses the y axis
