Flip, Then Shift
Part of the Functions & Transformations section of Coddy's Algebra 2 journey. Lesson 41 of 58.
Flips and shifts combine, and the rule tells you the order. In y = -f(x) + 5 with f(x) = x^2, you work out f(x), make it negative, then add 5. So the graph flips first and then moves up 5.
Follow the vertex: (0, 0) flips to (0, 0), then rises to (0, 5). One step right, f gives 1, the flip gives -1, and adding 5 gives 4: the point (1, 4). The curve opens down from its top point at (0, 5).
Compare y = -(f(x) + 5). Here the brackets add 5 first and the minus flips the result, so the top point lands at (0, -5). Read the rule the way you would work out a number, and the order of the moves comes with it.
Challenge
Draw the graph of y = -f(x) + 3 for f(x) = x^2. The faint curve is f itself. Drag the vertex, then the second point.
Try it yourself
Draw the graph
This lesson includes a short quiz. Start the lesson to answer it and track your progress.
All lessons in Functions & Transformations
4Combining Functions
Adding FunctionsSubtracting FunctionsMultiplying FunctionsAt a Single NumberRecap: Combining10Functions in Stories
Writing the RuleUsing the RuleWorking BackwardUndoing a ConversionRecap: Stories2Expressions as Inputs
A Letter as InputA Sum as InputShifting the InputSolving f(x) = kRecap: Inputs as Expressions5Composition
One Inside AnotherOrder MattersA Function of ItselfComposing RulesBreaking ApartRecap: Composition8Stretching and Flipping
Taller and FlatterFlipping OverFlip, Then ShiftReading the RuleRecap: Stretch and Flip