y = 90 − 15 x x ∈ { 0 ; 1 ; 2 ; 3 ; 4 ; 5 ; 6 }
The equation representing the amount owed after borrowing $90 and paying back $15 each week is 15 x + y = 90 . This is derived from the initial amount borrowed and the weekly payments. The equation is in standard form, where y is the amount owed after x weeks.
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