Solution to problem of creating a valid triangle where partial length of one side is missing

[Erik Norvelle]

Greetings,

I have come across a situation where I need to solve for distance x needed in order to complete a third side of a triangle in order to make it valid and graphable.

Given two sides A and B, and a partial third side C, where the three sides as given cannot form a valid triangle, I need to find the value for x that when added to C will make it possible to create a valid triangle whose area can be calculated and which can be graphed.

Attached is a graphic of the problem.

If I have made a stupid mistake here, my apologies... my mathematical knowledge extends to high school geometry and first-year college calculus.

TKA and cheers,

Erik

[Erik Norvelle]

Note that in the graphic as given here, it looks like the triangle could be created with length C as is. However, the general problem involves situations where the lengths of A and B make it impossible for C to be a valid side length, and as a result an additional length x must be calculated.