There are four cases:
Case 1:
That's this graph:
Case 2:
That's a parabola throu the origin opening left with vertex
Case 3:
That's a parabola thru the origin opening down with vertex
Case 4:
Complete the square on both sides by adding 1/4
to both sides:
Using the +
which was also part of case 1, so we have already graphed it.
Using the -
So we draw that line and the graph is complete:
That's two straight lines thru the origin. The first we have
already graphed in case 1. So we graph y=-x-1:
You must admit! -- that graph is COOL!
Edwin
