7/9=b/b-10 please help!!

7. the area of the playing surface at the olympic stadium in beijing isof a hectare. what area will it occupy on a plan drawn to a scaleof 1: 500?

V=x^4-y^4 pick three expressions that can represent the three dimensions of the prism (each in meters)

Point a (7,3) is translated to a'(16,-9). which rule describes the translation?