Question 1118692
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I will assume the quadrilateral is ABCD, although you didn't say so.  You might/will get different answers if the quadrilateral is ABDC, or ACBD, or....<br>
(1) From A to B is 3 units right and 1 unit down.
(2) Therefore, from D to C must be 3 units right and 1 unit down.
(3) The y coordinate of C is 3; if D to C is 1 unit down, the y coordinate of D must be 4.
(4) The x coordinate of D is 1; if D to C is 3 units right, then the x coordinate of C must be 4<br>
Answers: x = 4; y = 4