How old am i if 300 reduced by 2 times my age is 130

What are “like terms”? why can we only add like terms?

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?

A10 inch cookie cake is divided into 8 slices. what is the area of 3 slices