PLEASE HELP! Will the given equation solve the problem? Choose all which will.

Problem: The sum of twice a number and −6 is 9 more than the opposite of the number. Find the number.
Equation: 2n − 6 = 9 − n

Problem: Anna drove 450 km in 6 hours. Find her rate of travel.
Equation: 450r = 6

Problem: Three times a number increased by 44 is the same as the opposite of the number. Find the number.
Equation: 3n + 44 = −n

Problem: Sara collects her change and realizes that she has five times as many dimes as quarters. The total amount for the change is $5.25. Find the number of quarters in her collection.

Equation: x + 10x = $5.25