A and C are the opposite vertices of a square ABCD, and have
coordinates (a,b) and (c,d), respectively. What are the coordinates
of the vertices B and D? What is the area of the square?
A 1 metre cube has one face on the ground and one face against a
wall. A 4 metre ladder leans against the wall and just touches the
cube. How high is the top of the ladder above the ground?
Is there a relationship between the coordinates of the endpoints of a line and the number of grid squares it crosses?
Then you need three more sides all the same length that meet at
the vertices and are at right angles to each adjacent side.