To solve this I will use substitution method.
First we need to find x so
X - 4 = 9
X -4 (+4) = 9 (+4)
X = 13
Now we can substitute 13 where there is an x in the second equation so instead of
2x - 3y = 11 it would be
2(13) -3y = 11
Now
26 - 3y = 11
26 (-26) -3y = 11 (-26)
-3y = - 15
Y= 5
To prove our answer we can do 2(13) - 3(5) = 11 which is 26 - 15 = 11
X = 13
Y = 5