What is the linear equation for the following table?

x h(x)
20 20
40 -100
60 -220
80 -340
100 -460

2 answers

(-100-20)/(40-20) = -6

so, the slope is -6, and we start with

h = -6x

But -6(20) = -120, and h(20) = 20. So

h(x) = -6x + 140

You can check to make sure this fits the other points as well.
Thank you so much @steve