solve rational equations (multiplication)

Question

3x^3/6y^2 * 4y^5/7x^4

multiply and find out what x can't be??? answer needed asap

Answer 1

Multiplies the tops and the bottoms just for the fun of it, rather than cancelling:

 

 12x^3 y^5                2  y^3

--------------- =      ----------

 42 x^4 y^2              7   x