What s the length of the arc for the half circle

Tina practice piano for 15 hours last month and 45 hours this month use multiplication to write a statement comparing me i was tina practice during the two months use addition to write a statement comparing the hours tina practice during the two months

Drag the tiles to the boxes to form correct pairs. not all tiles will be used. match each set of vertices with the type of quadrilateral they form

How do you determine if an ordered pair is a solution to a given equation?