Question 39885
Let the 3 integers be x, x+1, x+2

x^2 + (x+1)^2 + (x+2)^2 = 77
x^2 + x^2 + 2x + 1 + x^2 + 4x + 4 = 77
3x^2 + 6x + 5 = 77
3x^2 + 6x - 72 = 0

*[invoke quadratic "x", 3, 6, -72]


Solving you get 4, -6

The 3 integers are 4,5,6 or -6,-5,-4