Problema Solution
Given the function f(x) = 3x - 9
a. Find the rate of change between the two stated values for x: 7 to 8
b. Find the equation of a secant line containing the given points: (7, f(7)) and (8, f(8))
Answer provided by our tutors
f(x) = 3x - 9
f(7)=3*7-9=12
f(8)=3*8-9=15
rate of change between the values of x:7 & 8=15-12=3
the two points are (7,12) (8,15)
equation of the straight line,
y-12=12-15/7-8 (x-7)
=>y-12=3(x-7)
=>y-12=3x-21
=>3x-y=21-12=9