Answer:
x ≥ 88
Step-by-step explanation:
In order to have at least an average of 80 after 4 tests, the sum of her scores must be at least 80 * 4 = 320 so we can write the following inequality:
71 + 78 + 83 + x ≥ 320
232 + x ≥ 320
x ≥ 88
Answer:
![x = \frac{y - 1150}{5}](https://tex.z-dn.net/?f=x%20%3D%20%20%5Cfrac%7By%20-%201150%7D%7B5%7D%20)
Step-by-step explanation:
![y - 1150 = 5x \\ \frac{y - 1150}{5} = x \\ x = \frac{y - 1150}{5}](https://tex.z-dn.net/?f=y%20-%201150%20%3D%205x%20%5C%5C%20%20%5Cfrac%7By%20-%201150%7D%7B5%7D%20%20%3D%20x%20%5C%5C%20x%20%3D%20%20%5Cfrac%7By%20-%201150%7D%7B5%7D%20)
Your 50 feet below sea level and then you go up 10 feet 5 times so the answer would be -10