Given:
Number of passengers seated in the roller coaster = 21
Empty seats = 3
Number of cars in roller coaster = 4 (each with the same number of seats)
To find:
An equation that can be used to determine the number of seats in each car.
Solution:
Let s be the number of seats in each car.
Total number of seats in 4 cars = 4s
Using the given information,
Total number of seats = Occupied seated + Empty seats
= 21 + 3
= 24
Now, the required equation is

Therefore, the required equation is
.
Divide both sides by 4.


Therefore, the number of seats in each car is 6.
Triangles CPA and CPB are both right triangles. They share a leg, so that leg in one triangle is congruent to that leg in the other triangle. We are given that PA is congruent to PB by the hash marks on the diagram. Thus two legs and an included angle are congruent between the triangles.
... ∆CPA ≅ ∆CPB by the SAS postulate
Then side CA ≅ CB = 15 in, because corresponding parts of congruent triangles are congruent (CPCTC).
... CA is 15 in.
45/3=15 45-15=30 30/5=6 3x6=18 30-18=12 the answer is 12