How to find the vertex: i keep getting (-1,3) what am i doing wrong y=x^2+2x+6

Which of the following is the formula for the sequence graphed below

Colby and jaquan are growing bacteria in an experiment in a laboratory. colby starts with 50 bacteria in his culture and the number of bacteria doubles every 2 hours. jaquan starts with 80 of a different type of bacteria that doubles every 3 hours. let x equal number of days. colbys experiment follows the model: a.) y=50*2^x b.) y=50*2^8x c.) y=50*2^12x jaquans experiment follows the model: a.)80*2^x b.)80*2^8x c.)80*2^12x

Rewrite the following quadratic functions in intercept or factored form. show your work. f(x) = 3x^2 - 12