How do you sketch the graph of #y=-2(x-3)^2+4# and describe the transformation?

1 Answer
Jan 31, 2018

Let's work backwards. First we need to identify the parent function: #x^2#

graph{y=x^2}

Let's shift the graph to the right #3# units

#y = (x-3)^2#

graph{y=(x-3)^2}

Now up #4# units

#y=(x-3)^2+4#

graph{y=(x-3)^2+4}

Now we can stretch this by a factor of #2#

#y=2(x-3)^2+4#

graph{y=2(x-3)^2+4}

Our last step is to flip the graph across the #x#-axis

#y=-2(x-3)^2+4#

graph{y=-2(x-3)^2+4}

Does this graph look the same as the equation we were given?

graph{y=-2(x-3)^2+4}

Yep, so we shifted the parent function #x^2# to the right by #3# and up #4#, then stretches it by a factor of #2# and then flipped it over the #x#-axis