To cross multiply rational expressions, there has to be one monomial in the left side of the equation and another monomial in the right side of the equation. For example, in this equation, we multiply 5 and x+4, as well as 3 and 6. This becomes 5x + 20 = 6. 5x = -14. x = -14/5 
Week 13 – Precalculus 11 – Cross-Multiplying with Rational Expressions
on