The price of a calculator has decreased from $200 to $150. what is the percentage of decrease?

Me figure out the process to determine x you appreciate it : )

Steve is scuba diving near his home in maui. at one point he is 100 feet below the surface. represent this number with a negative number. if he descends another 5 feet, what negative number will represents his.

What values of x satisfy the inequality x^2-9x< 0? how is your answer shown on the graph?