One factor of f(x)=5x^3+5x^3+5x^2-170x+280 is (x + 7). what are all the roots of the function? use the remainder theorem.

On a piece of paper graph f(x)=5•(0.4)^x

Aretha wanted to gather data about the cost of local bowling leagues in her area. she plotted the data and determined that the average bowling league costs consist of a one-time registration fee and a monthly fee modeled by the equation y = 15x + 20. identify and interpret the y-intercept in this model. the y-intercept is 20. this is the cost per month. the y-intercept is 20. this is the cost of registration. the y-intercept is 15. this is the cost of registration. the y-intercept is 15. this is the cost per month.

Ineed with question three. i don't understand how i'm supposed to achieve 3 marks.