Answer: the larger tank holds 38 gallons and the smaller tank holds 17 gallons.
Step-by-step explanation:
Let x represent the number of gallons of the toxic solvent that the larger tank holds.
Let y represent the number of gallons of the toxic solvent that the smaller tank holds.
The two tanks hold a total of 55 gallons of a toxic solvent. This means that
x + y = 55
One tank holds 4 gallons more than twice the amount in the other. This is expressed as
x = 2y + 4 - - - - - - - - - - - - -1
Substituting x = 55 - y into equation 1, it becomes
55 - y = 2y + 4
2y + y = 55 - 4
3y = 51
y = 51/3
y = 17
x = 55 - y = 55 - 17
x = 38
