Answer:
Total cost C = 12x dollars
Explanation:
Given;
A pound of candy costs x dollars.
x represent the price of one candy
One of the friends bought 5lb;
Cost C1 = 5lb × x dollars/lb
Cost C1 = 5x dollars
The second friend bought 7lb candies for the party;
Cost C2 = 7lb × dollars/lb
Cost C2 = 7x dollars
The total cost is the sum of the two costs;
C = C1 + C2
C = 5x + 7x
Total cost C = 12x dollars