Construction

Step 1: Draw a line of length and a circle with center and central angle over the chord . Measure out the point on the circle at distance from .

Step 2: Let the point be the intersection of and the right bisector of .

Then satisfies the given conditions.

Verification

Let and .

By construction, . By step 2, , so , the difference of the other sides.

Since the central angle by construction, . The line bisects the angle at . In any triangle, the , ; since is isosceles, . So and .