Question

I would really appreciate some help, please!

Lori has $450 in her bank account. She withdraws $20 a month for her gym membership. Construct a linear equation to model Lori’s bank balance for any given month.

Answer 1

Equation: y=20x+450

Use Desmos to graph it

Answer 2

y=-20x+450

Explanation:

Since Lori has 450$ initially, this can be modeled as our y-intercept of our function, or the b in y=mx+b. Since she's withdrawing 20$ a month to pay for the membership, she's losing 20$, which is why the 20 is negative in the equation. Let x be any amount of months, and y will be the balance of Lori's account at that month x.