Answer:
What do ya need help with?
Step-by-step explanation:
Do you want to solve for x and y?
What is the objective?
Answer:

Step-by-step explanation:
First of all, the number before the decimal would be the whole number of the fraction.
So, 
Then, you would put 0.83 over a fraction.
So because you cannot simplify it anymore, it would be 
Answer: 2.7d + 24.3
Step-by-step explanation: Easy
Answer:
Step-by-step explanation:
Givens
Greeting Card = 3.79
Total Cost = 5.11
Post cards = x
Equation
Total Cost = Greeting Card + 4x
Solution
Substitute the gives into the equation
5.11 = 3.79 + 4x Subtract 3.79 from both sides
5.11 - 3.79 = 3.79 - 3.79 + 4x Combine
1.32 = 4x Divide by 4
1.32/4 = 4x/4
x = 33
Each post card costs 0.33 dollars