9/10+9/10 must be in a form of a reduced proper fraction or mixed number

What are the measures of ∠a, ∠b, ∠c and ∠d? explain how to find each of the angle measure.

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?

Which of the following is correct interpretation of the expression -4+13