Answer:
The cost of 12 gallons of gas and a quart of oil is 14·x - 30
Step-by-step explanation:
When adding variables, the coefficient of the variables are added followed by multiplication of the sum of the coefficients with variable as follows;
The cost of 12 gallons of gas = 12·x
The cost of a quart of oil is represented by 2·x - 30
Therefore, the cost of 12 gallons of gas and a quart of oil can be represented as follows;
12 gallons of gas and a quart of oil = 12·x + 2·x - 30
Which gives;
The cost of 12 gallons of gas and a quart of oil = 14·x - 30.
