How do I find an average in algebra?

What is the greatest common factor of 8 and 36

Problem melissa is her dad build a walkway in their backyard. the walkway will be 54 feet long and 1.5 feet wide. the local hardware store sells tiles which are 1.5 by 1.5 feet and come in boxes of 12. how many boxes of tiles do they need?

Given that ot =5, xt=12, and ox= 13 is xy tangent to circle o at t? explain.