How do you graph y=x^2-2x+3?

1 Answer
Dec 29, 2014

You can look at the "special" points of your function. These are points that characterize the curve represented by your function.
In your case you have a quadratic in the general form given as:
y=ax^2+bx+c
which is represented, graphically, by a PARABOLA. The orientation of the parabola is given by the coefficient a of x^2; in this case you have a=1>0 so this is an upward parabola, i.e. like a U.

Now the special points:
1) You find the VERTEX (the lowest point of your parabola) which has coordinates given by:
x_v=-b/(2a) and y_v=-Delta/(4a);
(Where Delta=b^2-4ac);
2) Y-axis intecept: The coordinates of this pont are given as: (c,0);
3) X-axis intercept(s): the coordinate of these intercepts (if they exist) are given by putting y=0 and solving the second degree equation:
ax^2+bx+c=0

In your case you have:
enter image source here
With only these points we can already plot our parabola:
enter image source here