Answer:
25
Step-by-step explanation:
so you replace all the x's with 15 and it becomes
2×15-5
2×15=30
30-5=25
3 parts water
clean:water=1:3
1:3=xcleaner:1gallon
1/3=xcleaner/1gallon
times 3gallon both sides
1gallon=3xcleaner
divide both sides by 3
1/3 gallon=xcleaner
therfor you need 1/3 gallon of cleaner