15$ I believe, as we can disregard the two original books (they have been payed for) leaving her to buy 1 book and having seven dollars, however if she needs $8 more you simply need to add 8+7.
Answer:
C) y=-1/4x
Explanation:
The grade of the path in the mountain is calculated by determining first the ratio between the rise over the run and multiplying the ratio by 100%.
For Path A:
grade = (rise / run) x 100%
grade = (1414/ 3535) x 100% = 40%
<em>Answer: 40%</em>
For Path B:
grade = (rise / run) x 100%
grade = (4.26 m/ 22 m) x 100% = 19.36%
Answer: 19.36%
