Adding and subtracting fractions

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?

What are the sotions to the quadratic equation 9x^2=4

Find the value of the variable and the length of each secant segment.