Answer:
h=2
a=4
k= -21
Step-by-step explanation:
your h and k are vertex . h= x coordinate of vertex and k= y
so formula for vertex coordinates is x= -b/2a and y= (4ac-b²)/4a
your a b c are 4 -16 and -5 respectively according to the main equation
your a is concavity which is the same number as the 'a' of the equation
