algebra
posted by bryce on .
tickets to a museum cost $5 for general admission and $2 with student ID. On Friday night 200 tickets were sold for $625. How many general admissions tickets were sold.

G + S = 200 Therefore:
G = 200  S
5G + 2S = 625
Substitute 200S for G in second equation and solve for S. Insert that value into the first equation and solve for G. Check by inserting both values into the second equation.