interpolation between two equations

I have two equations corresponding for two values 8 and 10. By using these two equations is it possible to find the equation for a third value 9 using interpolation

Answer 1

[Image Analyst]

Let me see if I understand your question by giving an example. For an example let's say equation #1, using 8, is

y = 8 * x;

and let's say equation #2, using 10, is

y = exp(10*x);

Now, you have a 9 and that's all you have, except for the unknown third equation of course that you're hoping to discover. For example, let's say that the equation #3 that you're hoping to discover is

y = 42 * cos(9*x) + log(9 * x) + 123;

So you're hoping to figure that out when all you have is a 9, and equation #1 and equation #2. Is that what you want to do? If not, please rephrase your question.

Answer 2

[Walter Roberson]

Average them ?