I'm curious if Logic Programs can do algebra

Question

I read a brief article about Prolog and Logic Programming. I\'m curious if Logic Programs can do algebra. Like would you be able to ask what the Variable of X is in the equa

Answer 1

How about this? Note that this will only work for X+Y=Z.

equation(X,Y,Z):- var(X),X is Z-Y.
equation(X,Y,Z):- var(Y),Y is Z-X.
equation(X,Y,Z):- var(Z),Z is X+Y.

You can ask:

equation(5,X,7).
X = 2 .
?- equation(2,5,X).
X = 7.
?- equation(X,5,7).
X = 2