Variable $x$ cannot be equal to $0$ since division by zero is not defined. Multiply both sides of the equation by $80x$, the least common multiple of $x,80,8$.
$$80\times 200=x\times 50\times \frac{4}{8}$$
Multiply $80$ and $200$ to get $16000$.
$$16000=x\times 50\times \frac{4}{8}$$
Reduce the fraction $\frac{4}{8}$ to lowest terms by extracting and canceling out $4$.
$$16000=x\times 50\times \frac{1}{2}$$
Multiply $50$ and $\frac{1}{2}$ to get $\frac{50}{2}$.
$$16000=x\times \frac{50}{2}$$
Divide $50$ by $2$ to get $25$.
$$16000=x\times 25$$
Swap sides so that all variable terms are on the left hand side.
