## anonymous 5 years ago Use a system of equations to solve the problem. There is an initiation fee to join the Pine River Country Club, as well as monthly dues. The total cost after 7 months' membership will be $3,050, and after 1-1/2 years,$3,930. Find both the initiation fee and the monthly dues.

1. anonymous

think of this as 'find the equation for the line through the points $(7,3050),(18,3930)$ the 18 because one and a half years is 18 months. the slope is the monthly dues, the y-intercept (what you get when x = 0) is the initiation fee.

2. anonymous

$m=\frac{3930-3050}{18-7}=\frac{880}{11}=88$ so it is $88 a month. 3. anonymous to find the y-intercept write $y-y_1=m(x=x_1)$ $y-3050=88(x-7)$ $y-3050=88x-616$ $y=88x+2434$ initiation fee is$2434