To use the Pythagorean theorem on Desmos, first enter the equation for the Pythagorean theorem into the equation box. For example, if you want to find the length of the hypotenuse of a right triangle with legs of length 3 and 4, you would enter "c^2 = a^2 + b^2" into the equation box. Then, enter the values for a and b (in this case, 3 and 4) into the equation. Finally, click the "Calculate" button to find the value of c (in this case, 5).
