Answer:
x = -2
Step-by-step explanation:

distribute

isolate variable (subtract 3x from both sides and 4 from both sides)

divide both sides by 5 to get x
x = -10/5 = -2
Answer:
n+12=31
n=31-12
n=19
Step-by-step explanation:
200 miles and 480 miles so the answer would be the second car travelled 280 miles further
Answer:
165 ways
Step-by-step explanation:
Selection deals with combination
There are a total of 11 from which 3 are to be selected
11C3 = 11!/3!(11-3)!
= 11!/(3!x8!)
=(11x10x9x8!)/(3x2x8!)
=11x10x9/6
=11x5x3 = 165 ways