The function of the of the graph is f(x) = 0.5x. ( option A)
The equation of a linear graph is expressed as
y = mx + b
where m is the slope and b is the y intercept. y intercept is the point where the graph cut the y axis.
slope of the graph = 1 - ( -1)/2-(-2)
slope = 2/4 = 1/2
slope = 0.5
y intercept = 0,
y = 0.5x + c
y = 0.5x + 0
y = 0.5x
y = f(x)
f(x) = 0.5x
Therefore, the equation of the function of the graph is f(x) = 0.5x