Since the line passes through the origin, when calculating the slope of the line, we can make use of the origin as a point. So pests say (x1, y1) = (0,0) and (x2,y2) is (a,b). Hence the slope is b/a.
Now we now act on this information to solve the problem. Firstly, we know that the slope is negative, this means either a or b is negative but both are not negative. Secondly, b is greater than a. This mean b is the positive term as both terms cannot be negative.
For any rectangle or square located on the axes, match the pairs and find what's missing. 3 -- 3, 4 -- 4. unmatched are 4 and 1. 4 is x because it's missing from x and same for 1 and y.
