What is the value of the expression 4x+y 2y−x when x = 2 and y = 4

The equation x2 – 1x – 90 = 0 has solutions {a, b}. what is a + b?

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

If g^-1(x) is the inverse of g (x) which statement must be true