Respuesta :

Answer:

-a

-------

10-a

Step-by-step explanation:

a

----

a-10

Multiply the top and bottom by -1

-1*a

-------

-1(a-10)

-a

------

-a+10

Rewriting

-a

-------

10-a

Answer:

-a/(10-a)

Step-by-step explanation:

To get from a - 10 to 10 - a,  you just have to multiply by -1.

So fi you multiply both the top and bottom by -1, you'd get -a/(10-a).