MATH HELP PLZ!!!

Question

A​ sparkling-water distributor wants to make up 200 gal of sparkling water to sell for $5.00 per gallon. She wishes to mix three grades of water selling for $8.00, $3.00, and $4.50 per​ gallon, respectively. She must use twice as much of the​ $4.50 water as the $3.00 water. How many gallons of each should she​ use?

Answer 1

x represents the amount of $3.00 water

2x represents the amount of $4.50 water

200 - 3x represents the amount of $8.00 water

3x + 4.5(2x) + 5(200 - 3x) = 5(200)

Can you solve for x and answer?