Answer:
Tickets of lawn seat sold = 900
Tickets of pavilion seat sold = 600
Step-by-step explanation:
Let
be the no. of lawn seats and
be the no. of pavilion seats.
According to the given question,
----eq 1 and
---- eq 2
After obtaining the two equations we can solve this by either substitution or elimination.
By substitution, put
from eq 1 to eq 2, and solve for y, which gives
and then substitute this value in eq 1 to get

By elimination, make the coefficient of one variable say x equal in both equations, for this multiply eq 1 with 15
now eq 1 becomes
subtract this equation from eq 2 to get
and substitute this value in eq 1 to get
