Two farmers were plowing along the edges of a triangular cornfield. They both started at the same corner of the field. The first farmer plowed directly West for 0.5 miles and then stopped. The second farmer doesn't know how far she traveled, but she knows it was N45E at a speed of 5 miles/hour for exactly 30 minutes. What was the area of the cornfield?

According to my diagram, they ploughed at an angle of 135° to each other, one went .5 miles , the other 2.5 miles

area = (1/2)(side1)(side2)(sin(angle between them))
= (1/2)((.5)(2.5)sin 135°
= .... square miles