Which expression is equivalent to ...

X2 + y 2 = 36 x + y = 6 solve the system of equations.

Arock was dropped from the top of a building. the function that describes the height after it was dropped is f(x)=64-16x^2. what are the zeros of the function and what do they mean?

Savannah talked for 6 minutes on the phone. catherine talked for n minutes. catherine talked 3 times as long as savannah. how long did nathan talk?