← Chapter 4
College Algebra · Chapter 4

Transformations: Shift, Stretch, Reflect

Every graph in this course is some parent function that has been moved, resized, or flipped. Master one formula — g(x) = a f(x − h) + k — and you can graph all of them without plotting a single table of values. Drag the three knobs and watch what each one actually does.

The graph

parent   current graph moved points the one we check

Where every point lands

1 · Pick a parent function

2 · Drag the three knobs

a  stretch / reflect1
−303
h  horizontal shift (inside)0
−606
k  vertical shift (outside)0
−606
Horizontal—
Vertical size—
Vertical shift—

3 · Build it up, one change at a time

The one rule to remember: changes outside the function (a and k) affect the outputs — heights — and do exactly what they say. Changes inside the function (h) affect the inputs and do the opposite of what they look like.