Find the sum of the fist 8 terms in the sequence?

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?

Apositive number a or the same number a increased by 50% and then decreased by 50% of the result?

What is the y-intercept of the line given by the equation