Answer:
16 singles, 56 couples
Step-by-step explanation:
There's two linear equations that we can make: one for money and one for people.
Let the number of single tickets be s and the number of couple tickets be c
.
We know that the amount of money we make is $ = 20
s
+
35
c
=
2280
We also how many people can come P =
1
s
+
2
c
=
128
We know that both s are the same and both c are the same. We have two unknowns and two equations, so we can do some algebra to solve for each.
Take the first minus twenty times the second:
20
s
+
35
c =2280
−
20
s
−
40
c
=
−
2560
−
5
c
=
−
280
⇒
c
=
56
Plugging this back into the second equation,
s
+
2
c
=
s
+
2
⋅
56
=
s
+
112
=
128
⇒
s
=
16
