Find the sum of 2ab and 9ab

Which statement describes surface features called maria on the moon

Which steps could be part of the process in algebraically solving the system of equations, y+5x=x^2+10 and y=4x-10

If you were constructing a triangular frame, and you had wood in the length of 4inches, 4 inches, and 7 inches, would it make a triangle? would you be able to create a frame from these pieces of wood? yes or no. explain your mathematical thinking