Transformations of functions: Vertical translations  Relations and Functions
Transformations of functions: Vertical translations
Vertical translations refer to movements of a graph of a function vertically along the yaxis by changing the y values. So, if y = f(x), then y = (x) + h results in a horizontal shift. If h > 0, then the graph shifts h units up; while If h < 0, then the graph shifts h units down.
Lessons

a)
Sketch the following functions on the same set of coordinate axes:
$\left( y \right) = {x^2}$, $\left( {y  3} \right) = {x^2}$, $\left( {y + 2} \right) = {x^2}$ 
b)
Compared to the graph of $y = {x^2}$:
• the graph of $\left( {y  3} \right) = {x^2}$ is translated "vertically" ________ units _____________.
• the graph of $\left( {y + 2} \right) = {x^2}$ is translated "vertically" ________ units _____________.


a)
$y = f\left( x \right)  8$

b)
$y = f\left( x \right) + 3$

c)
In conclusion:
• $\left( y \right) \to \left( {y + 8} \right)$: shift ________ units ______________ $\Rightarrow$ all $y$ coordinates _____________________________.
• $\left( y \right) \to \left( {y  3} \right)$: shift ________ units ______________ $\Rightarrow$ all $y$ coordinates _____________________________.
