The sum of godfrey's age and marilyn's age is 60 years. ten years ago, godfrey was 3 times as old as marilyn was then. how old is each now?

Which is a graph of a proportional relationship?

Which equation results from adding the equations in this system? x+6y=9 and -x+2y=-15

He mass of a single atom of carbon can be found by dividing the atomic mass (12.01 g) by 6.022 x 10^23. which is the mass of a single carbon atom, correctly written in scientific notation with the correct number of significant figures?