Pi really goes on for infinity, but here are the first seven numbers:
3.14159
He would need 11.1 gallons of gas if he was/would drive 296 miles.
12 divided by 320 = .0375
.0375 x 296 = 11.1 Gallons of Gas needed to drive the distance.
If the number of adult tickets are taken as x then the number of children’s tickets can be taken as (89 — x ) then we can set up the equation
4.10(x) + 2.70 (89 — x) = 331.30
4.10x + 240.3 — 2.70x = 331.30
1.4x = 331.30 — 240.30
1.4x = 91
X = 65
Therefore 65 adult tickets and 24 children tickets as 89 — 65 is 24
For this case, we have the following expression:

We simplify the expression:
If we add similar terms, taking into account that different signs are subtracted and the sign of the greater one is placed, we have that 
So, we have to:

Answer:
-3x + x + 5 = -2x + 5