What is the axis of symmetry of the function f(x)=-(x+ 9)(x-21)

There are several unique characteristics of qualitative research that make it distinct from quantitative research. describe the aspects of qualitative research and the elements of design that contribute to the rigor of the work. what actions of the researcher can compromise the integrity of the findings?

Why do interests rates on loans to be lower in a weak economy than in a strong one

James was playing a game with his friends. he won 35 points. then he lost 15, lost 40 and won 55. how did he come out