Answer:
![y = 120 + 0.15x](https://img.qammunity.org/2021/formulas/mathematics/high-school/wbsn7lw78x493kqkm0gn48bgu4215r3loj.png)
Explanation:
Given
per vertical meter
per x meter
![x = vertical\ meter](https://img.qammunity.org/2021/formulas/mathematics/high-school/pkzn6b8lu0y6t2yvy3rlym9g4j5ga6es10.png)
For:
---
![y = 645](https://img.qammunity.org/2021/formulas/mathematics/high-school/ek9whsan0rne96jyero6108sbxbd506x1r.png)
Required
Determine the equation that relates y to x
Let the initial fee be represented with m
The equation that relates y to x is:
![y = Initial\ Fee + Additional\ Fee * Vertical\ Meter](https://img.qammunity.org/2021/formulas/mathematics/high-school/grdvyo7pcqksmvvk14uphqsx12eizc291d.png)
This gives
![y = m + 0.15 * x](https://img.qammunity.org/2021/formulas/mathematics/high-school/xvobnpi4kw9pf6kd7lfffgrnl2cr74z87i.png)
We need to first solve for m
From the question,
when
![y = 645](https://img.qammunity.org/2021/formulas/mathematics/high-school/ek9whsan0rne96jyero6108sbxbd506x1r.png)
So:
![645 = m + 0.15 * 3500](https://img.qammunity.org/2021/formulas/mathematics/high-school/m5hyr3yqnr9wl6draanq3den1hcsdlfq28.png)
![645 = m + 525](https://img.qammunity.org/2021/formulas/mathematics/high-school/j2bjfk8alg94dfrnx3auboa1o0j45yohyf.png)
Make m the subject
![m = 645 - 525](https://img.qammunity.org/2021/formulas/mathematics/high-school/54j03ygovj3m4csc0h9xwjeb6jh6fcxz8a.png)
![m = 120](https://img.qammunity.org/2021/formulas/mathematics/high-school/ntqz6af4zv7rnfrdmq13scurwwqqi4p3wf.png)
So, the initial fee is $120
Substitute 120 for m in
![y = m + 0.15 * x](https://img.qammunity.org/2021/formulas/mathematics/high-school/xvobnpi4kw9pf6kd7lfffgrnl2cr74z87i.png)
![y = 120 + 0.15 * x](https://img.qammunity.org/2021/formulas/mathematics/high-school/hewaazv0cv2h4ktfsxjrx18oho7u6ubgt2.png)
![y = 120 + 0.15x](https://img.qammunity.org/2021/formulas/mathematics/high-school/wbsn7lw78x493kqkm0gn48bgu4215r3loj.png)
Hence, the required equation is:
![y = 120 + 0.15x](https://img.qammunity.org/2021/formulas/mathematics/high-school/wbsn7lw78x493kqkm0gn48bgu4215r3loj.png)