A linear function has the form y = ax + b
In this case, x is the price and y is the demand.
And you can state the values of the constants a and b if you know two points.
Here you know the points (134, 96) and (100, 112).
Using (134, 96) you get 96 = 134a + b
Using (100, 112) you get 112 = 100a + b
Now you just have to solve that system of two equations.
subtract the second from the first:
112 - 96 = 100a - 134a = > -34a = 16 = a = - 16 / 34 = -8/17
And now you can find the constant b from any of the two equations of the system:
b = 112 - 100a = 112 - 100(-8/17) = 112 + 800/17 = [1904+800]/17 = 2704/17
=
The the equation if -8/17 x + 2704/17
Answer: -(8/17)x + 2704/17
