y = 2x + 1
2y + x = 2
2y = -x + 2
y =(-1/2)x + 1 , both have the same y-intercept of (0,1)
So one vertex of the rectangle is (1,0)
Pick any other point on each of the lines and draw the lines
since the slopes of the two lines are negative reciprocals of each other you must have a 90° angle at (1.0)
So all you have to do is create the two lines through (6,3) that have slopes of 2 and -1/2.
1st line: from (6,3) step 1 to the right, then up 2
mark that point, draw line through (6,3) and extend
2nd line: from (6,3) step -2 to the left, then up 1, mark that point, draw the line through 6,3.
There is your rectangle!