2025 AIME II Problems/Problem 14
Solution 1(Coordinates and Bashy Algebra
By drawing our the triangle, I set A to be (0, 0) in the coordinate plane. I set C to be (x, 0) and B to be (0, y). I set K to be (a, b) and L to be (c, d). Then, since all of these distances are 14, I used coordinate geometry to set up the following equations:
+
= 196;
+
= 196;
+
= 196;
+
= 196;
+
. = 196. Notice by merging the first two equations, the only possible way for it to work is if
=
which means
. Next, since the triangle is right, and we know one leg is
as
, the other leg, x, is
.Then, plugging these in, we get a system of equations with 4 variables and 4 equations and solving, we get a = 2, b = 8
, c = 13, d = 3
. Now plugging in all the points and using the Pythagorean Theorem, we get the coordinates of the quadrilateral. By Shoelace, our area is 104
. Thus, the answer is
.
~ilikemath247365