y = x^2 – 10x + 21. So the table of values looks like this:

x………………y

2……………..5

3……………..0

4…………….. -3

I`m sure you can complete it ! ! !

Now complete the table, and using appropriate scales,

usually 2cm to represent one unit on each axis, you can plot

the graph. Hope this helps, Twiggy.

First, to find where it hits on the x-axis you to set y to 0 (zero). The only way y can equal zero is if one of the sets in the parentheses equals zero. So by this, you can gather that y is zero when x=7 (7-7=0) or when x=3 (3-3=0).

Now you have your points on the x-axis. To see if it opens up or down, you merely need to figure out where it hits the y-axis. At the y-axis, x is zero, right? so y = (0-7)(0-3) or -21. Since the two points of the curve hit the x-axis at 3 and 7, both to right of the y-axis, you know that this is outside those two points, and thus not part of the bell, but part of the extension, and thus it opens down.

That should do it. If any part of that was unfathomable gibberish, I apologize. I need to go to bed.

………..then using shifting of origin and intercept method plot its graph