Jonah has a large piece of land in the country. His land is a square plot and the northern edge is in a perfect east/west line (so is the southern edge if you think about it). The road enters his land at a point on the western edge 3 miles due south of the northwest corner and 7 miles as the crow flies from the north east corner. What is the area of the land in square miles?
If I understand your question, you have a right-angle triangle with one side=3 and the hypotenuse =7.
So, by Pythagoras's Theorem:
7^2 - 3^2 =T^2, T=Third side
T =6.325 miles.
Area of this triangle = 6.325 x 3 / 2 =~9.487 miles^2
Since the property is a square, then:
Total area of Jonah's property=9.487 x 2 =~18.974 miles^2.