Question

Each day that a library book is kept past its due date, a $0.30 fee is charged at midnight. Which ordered pair is a viable solution if x represents the number of days that a library book is late and y represents the total fee?

(–3, –0.90)

(–2.5, –0.75)

(4.5, 1.35)

(8, 2.40)

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Answer 1

Option four(8, 2.40) is the correct answer because it satisfies our equation;

Y= 0.30 * X

2.40= 0.30 * 8

2.40 = 2.40.

Fourth option (8, 2.40) is the only viable solution to this question.

Answer 2

(8, 2.40)

Explanation:

Actually, in this problem we just have to apply common sense.

The question is asking for the ordered pair that is viable where x days.

If x represent days, then viable coordinates must have whole number, only positive, because negative days don't make sense, and decimal days also don't make sense to this problem.

So, the only option with this qualities is the last option, that's the solution.

In addition, we also can find a linear relation and see which point satisfies it. The linear relation for this problem would be:

y = 0.30x, that is, $0.30 per day.

If we use x = 8, and replace it, we find that is solution:

y = 0.30(8)=2.4.

Therefore, the last option is which satisfies the linear relation.