Answer:
Associative Property of Addition
Step-by-step explanation:
From the list of given options, option A correctly answers the question and this is because
--- (1)
or
--- (2)
<em>The above illustrations only apply to Associative Property of Addition</em>
In Crystal's case:

This can be compared to (1) above
Hence;
<em>Option A answers the question</em>
To justify the yearly membership, you want to pay at least the same amount as a no-membership purchase, otherwise you would be losing money by purchasing a yearly membership. So set the no-membership cost equal to the yearly membership cost and solve.
no-membership costs $2 per day for swimming and $5 per day for aerobic, in other words, $7 per day. So if we let d = number of days, our cost can be calculated by "7d"
a yearly membership costs $200 plus $3 per day, or in other words, "200 + 3d"
Set them equal to each other and solve:
7d = 200 + 3d
4d = 200
d = 50
So you would need to attend the classes for at least 50 days to justify a yearly membership. I hope that helps!
Answer:
Amphitrite1040
Step-by-step explanation:
<h3>Answer:</h3>
13 years old
<h3>Explanation:</h3>
Let g and m represent grandfather's age now and my age now. The relation 5 years ago was ...
... g -5 = 5(m -5)
The relation in 3 years will be ...
... g +3 = 3(m +3)
Subtracting the first equation from the second, we get ...
... 8 = -2m +34
... 2m = 26 . . . . . add 2m-8
... m = 13
My age now is 13.