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Interpret the following expression (5y^2-7)^3/(2y)^2

At noon a tank contained 10cm water. after several hours it contained 7cm of water. what is the percent decrease of water in the tank?

Table of values relation g values x, y 2,2 /3,5 /4,9 /5,13 which ordered pair is in g inverse? a(-2,2) b(-3,-5) c)4,9) d( 13,5)