Question 1208166
.
The domain and range of a relation are the sets of all the x-coordinates and all the y-coordinates of ordered pairs respectively. 

Given set A = {(2,3), (4,5),(7,6), (8,9),find the domain D and the range R. 


I say the following:

D = {2, 4, 7, 8}

R = {3, 5, 6, 9}


You say? 
~~~~~~~~~~~~~~~~~~~~~



You correctly determined the sets D (domain) and R (range).


Notice that in your post you opened the curved bracket { for set A, 
but forgot to close it using closing bracket }.



In this connection, let me tell you one ancient story about accuracy of writing.



In one country,  a ruler was presented with a petition for clemency from a man sentenced to death.


On the petition,  the ruler wrote his decision/directive: 


            " To execute is impossible to pardon ", 


but forgot to put a comma in the right place.


Those who were supposed to carry out the directive were perplexed - what should they do?



            Since then,  this story became an historical anecdote

                      to teach those who write inaccurately.