Which statement correctly explains why this is a function?

Mr. brettler is hanging up a 5-foot tall rectangular welcome sign in the gym. he has drawn a sketch on a coordinate grid. he has the lower vertices of the sign at (9, –3) and (–6, –3). where would the upper vertices be on the grid?

Need showing work for this problem 56.25 ×25.80

What are two numbers that have a sum of 15