8 True or False: The substitution method is a method of solving systems of equations by adding equations together in such a way that the variables are set aside, one by one.

Me because some of question i don’t understand

Bob is putting books on a shelf and takes a break after filling 18 1/2 inches on the book shelf. the book shelf is now 2/3 full. how long is the entire bookshelf?

Tim knows the volume and base area of a wooden chest that is in the shape of a rectangular prism. if the volume is 524 cubic unit and the base area is 15 square unit, what is the height of the chest? 124 unit 1124 units 112 unit 1112 units