I need help with number 16, and 18.

Which best explains why this triangle is or is not a right triangle?

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?

Finding tbe values of the variables in each kite