Y=((x-5)(x-4))/(x-4)
y=x-5
Simple....
you have:

to convert them into
improper fractions:
1.) Take whole number*denominator
(5*5=25)
2.) Take what you got...and
add the numerator
(25+2=27)
3.) Use the original denominator

Do the same to the other one...
2*13=26
26+10=36

Now..add...

But..you need a common denominator!


Now you can add!

When simplified....

Thus, your answer.