Answer:
#17 25 rounds
#18 8 months
Explanation:
17. GOLF
Let x be the break-even number of rounds of golf played when both costs are the same. Breakeven refers to the number that will make both costs equal
Let C be the cost
With membership, we have $500 membership fee and 35 per round for x rounds:
C = 500 + 35x (1)
Without membership:
C = 55x (2)
For both costs to be the same, set eq (2) = eq (1)
(2) = (1)
55x = 500 + 35x
Subtract 35x from both sides:
55x - 35x = 500 + 35x - 35x
==> 20x = 500
Divide above by 20 to get the answer
20x/20 = 500/20
x = 25
So number of rounds of gold to be played for both costs to be the same = 25 rounds
18. MUSIC
Let x be the number of months when both CD collections have the same numbr of CDs
- Marc starts with 45 CDs. If he buys 4 CDs a month, then total he buys in x months = 4x
At the end of x months Mark's total CD collection = 45 + 4x (1)
- Corinna starts off with 61 CDs. She purchases 2 CDs per month, so in x months she would have purchased 2x CDs
At the end of x months Corinna's total CD collection = 61 + 2x (2)
- For both numbers to be equal, set Eq (1) = Eq (2) and solve for x, the number of months
(1) = (2) ==> 45 + 4x = 61 + 2x
- Subtract 2x from both sides:
45 + 4x -2x = 61 + 2x -2x
==> 45 + 2x = 61
- Subtract 45 from both sides to isolate the x term
45 + 2x -45 = 61 - 45
==> 2x = 16
- Divide both sides by 2 to solve for x
2x/x = 16/x
==> x = 8 - So it will take 8 months for both counts of CD collections to be the same
Hope that helps and please ask for any clarifications