Maple: simplification expression with some assumption

Question

I need to to some transformation of expression. I have W:=ax+by+cz. Now I want to set ax=0.5x, by=-0.5*x. After that I need to get W. Can I do it using Maple?

Answer 1

Here are two ways to handle your example,

W := a*x+b*y+c*z:

eval(W, [a*x=0.5*x, b*y=-0.5*x]);

       c z

simplify(W, [a*x=0.5*x, b*y=-0.5*x]);

       c z

Note that your syntax is unclear. I can't tell whether you have the names ax and by or the products a*x and b*y.