# Open Middle Triangle Angle Sum Problem

- Author:
- Tim Brzezinski

## Creation of this resource was inspired by this Open Middle problem by Franco D. Adkins:

Using the digits 1-9 at most one time each, fill in the blanks so that when you solve for , it is a whole number.
You can use the app below to create such a triangle that's drawn to scale. Use the sliders to change the values of the digits (blanks) in each algebraic expression (for and ).
**How many solutions can you find? List them here: **

## You can create different variations of this problem by unlocking angle C and changing its measure.

## Teachers:

For a version without the

**Show angle measures**checkbox (lower left), click here.