A) This is a linear function and the equation of the graph is conventionally y = mx + c where m is gradient and c is intercept on y axis
In this function, the equation of the graph is
y = 4x + 1
B) This is a quadratic function and it takes the form:
where a = -1, b = 4 and c = -2. Thus the equation of this line is:
C) This is an exponential function. The c(x) value increases with the increasing powers of 3.