3x + 9 = 90
3x = 90 - 9 = 81
x = 81/3 = 27
x = 27
36.89 total divided by the 8.6 gallons he bought = 4.2 so the price per gallon would be $4.20
The answer is m = -59/42
Step by step explanation is in the image below.
I think this question is a part of another question; you can have any ratio that can add up to 114 cm.
-4x+3+2x-6
The answer is -2x-3