Hello I'm Teacher Reynan
First you have to cancel letters C and D in the numerator and denominator, to get
2a + b - 2a - b / x - 3y - x + 3y then combined similar terms, then
2a - 2a +b -b / x - x - 3y + 3y the answers in both numerator and denominator is zero
0 / 0 is indeterminate or undefined
2ac+bc-2ad-bd/cx-3cy-dx+3dy
in solving this, you have to factor it first
2ac+bc-2ad-bd
c(2a+b) - d(2a+b), it is the same as (2a+b)(c-d)
factor also cx-3cy-dx+3dy
c(x-3y)-d(x-3y), the sign isnegative because if you mulipied -d to -3y the answer is 3dy, this factor is the same as (x-3y)(c-d)
we have arrived in this equation,
(2a+b)(c-d)/(x-3y)(c-d) , you can cancel out the numerator and the denominator(c-d) because when that two is divided, the answer is one.
so the answer is 2a+b/x-3y