Step-by-step explanation:
horizontal lines will have a gradient(m) of 0
so if m=0 , the line is horizontal
formula to find m:
m=y2-y1 / x2-x1
insert coordinates into formula

As m=0 , therefore it is a horizonta line.
hope this helps..
I think it’s two, counting the lines
Answer:
!!!
Step-by-step explanation:
Graph 1: -3 is the slope
Graph 2: 4/5 is the slope
"When you calculate the average rate of change of a function, you are finding the slope of the secant line between the two points. f(x) = x2 and f(x + h) = (x + h) Therefore, the slope of the secant line between any two points on this function is 2x + h."