how do you subtract an integer from another integer without using a number line or counters? give and example

Aiden drives to school and back each day. the school is 16 miles from his home. he averages 40 miles per hour on his way to school. if his trip takes 1 hour, at approximately what speed does aiden drive home?

Awasher and a dryer cost $701 combined. the washer costs $51 more than the dryer. what is the cost of the dryer?

Use complete sentences to differentiate between a regular tessellation, and a pure tessellation. be sure to include specific types of polygons in your explanation.