Incenter of a Triangle Formula

Equation for calculate incenter of a triangle is,

X = (a * x1 + b * x2 + c * x3) / (a + b + c)
Y = (a * y1 + b * y2 + c * y3) / (a + b + c)

X = X-Coordinate points
Y = Y-Coordinate points
a, b, c = Positive Real Numbers
x1, x2, x3 = Coordinate Points
y1, y2, y3 = Coordinate Points