Answer:
[tex]\displaystyle-\frac{a}{b}[/tex]
Step-by-step explanation:
We have:
[tex]\displaystyle{\frac{a(x-2y)}{b(2y-x)}[/tex]
In the denominator, we can factor out a negative 1. This yields:
[tex]=\displaystyle\frac{a(x-2y)}{-b(x-2y)}[/tex]
We can now cancel out the factor. Hence:
[tex]\displaystyle=-\frac{a}{b}[/tex]