Answer:

Step-by-step explanation:
Let x represent the number of times Giselle uses the athletic club and y represent money left in account.
We have been given that each time she uses the club, $15 is deducted from the account. The amount used after using the club after x times would be
.
We are also told that Giselle pays $220 in advance on her account at the athletic club.
The money left in account after x uses of athletic club would be money in account initially minus amount used for using the club x times.

Therefore, our required equation would be
.
Depends on the calculator you have at your disposal. If it's one of the TI-83 series, you can use the built-in 'fnint' function.
https://brownmath.com/ti83/integr.htm
Perpendicular = opposite sign and reciprocal slope
Slope 2 turns into -1/2
Y = -1/2x + b
Plug in the point
-5 = -1/2(2) + b, b = -4
Solution: y = -1/2x - 4
Answer:
○ 
Step-by-step explanation:

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