Find the x coordinate of the vertex of the parabola sketched in the figure below ? PLEASE HELP!

If you roll two fair dice (one black die and one white die), in how many ways can you obtain a 4 on at least one die?

Dylan and dusty plan to take weekly surfing lessons together. if the 2-hour lessons are $20 per person and they plan to spend $100 each on new surfboards, what is the maximum number of lessons the two can take if the total amount spent for lessons and surfboards is at most $480?

Which expression gives you the distance between the points (5,1)and(9,-6)