Slope of Secant line-Functions

Question

Graphing point (4,f(4)),(0,f(0)), Find the slope of the secant line from x_(1)=0,to x_(2)=4, f(x)=1.2x^(3)-34x^(2)+261x+550

Answer 1

f(0)=550

f(4)=1126.8

secant line goes through two points (0, 550) and (4, 1126.8)

y intersept is 550

slope is (1126.8-550)/4=144.2

equation of the secant line is y=550+144.2x