B. R.Ramachandran wrote...
What kind curves are they (i.e., what kind of functions are those trendline
equations) - linear, polynomial, logarithmic, ....? Can you post sample
trendline equations for the pump curve and the system curve?
....

It doesn't matter what kind of curves they are if they're both
functions of a single, common variable (otherwise they couldn't be
graphed together easily). All that's needed is one cell containing the
common X value, one cell for each curve containing the f(x) and g(x)
function values given the common X value and their other respective
parameters, and finally another formula cell calculating the difference
between the two function values. Then use Solver to set that last cell
to zero by changing the X value cell. If the two curve intersect
transversally, Solver shouldn't have any difficulty finding the
intersection point's X value, and both functions will return the same Y
value.

If the two curve intersect nontransversally, e.g., two circles
intersecting at a single point, then Solver might have some difficulty
and the OP would need to play with its options.

"Cadelima" wrote:
I am trying to otain a solution for the number where two curves meet.
Specifically trying to determine the expected flow rate given a pump curve
and system curve. The curves shift depending on variables that are read from
a spreadsheet. I can get the curve formulas by graphing them and requesting
the trendline feature, but then I have to manually enter the curve formulas,
set them equal to each other, and solve the equation. Can Excel do this
automatically from two data sets? Any help would be appreciated.