$30 because you are taking away 20% of $30 and then adding back that 20%.
Answer:
Step-by-step explanation:
Given

Required
Make t the subject

Cross Multiply


Collect Like Terms

Factorize:

Make t the subject

Answer:
x=-1,y=0
Step-by-step explanation:
-10y+9x=-9
10y+5x=-5
14x=-14
x=-1
-10y-9=-9
y=0
55.50 divided by 2 = 27.75
Only ask about the cost of tickets.