Hello everyone,
I have 2 questions which I would appreciate if someone could answer. Thank you very much!
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1. Dave can mow his lawn in 20 minutes less time with his power mower than with his hand mower. One day his power mower broke down 15 minutes after he started mowing, and he needed 25 minutes more time to completeh the job with his hand mower. How many minutes does Dave take to mow the lawn with the power mower?
I set up the following equation: \(\displaystyle \frac{15}{x}\ + \frac{25}{x + 20}\ = 1\), which gave me \(\displaystyle x = 30\). The answer was \(\displaystyle x = 50\) and the equation in the answer key was \(\displaystyle \frac{15}{x - 20}\ + \frac{25}{x}\ = 1\).
Why doesn't my equation work?
2. The graph below represents the graph of y = f(x). Which is the graph of y = f(-x)?
I don't understand why the graph of y = f(-x) is exactly the same as y = f(x).
The graph can be found here:
I have 2 questions which I would appreciate if someone could answer. Thank you very much!
---
1. Dave can mow his lawn in 20 minutes less time with his power mower than with his hand mower. One day his power mower broke down 15 minutes after he started mowing, and he needed 25 minutes more time to completeh the job with his hand mower. How many minutes does Dave take to mow the lawn with the power mower?
I set up the following equation: \(\displaystyle \frac{15}{x}\ + \frac{25}{x + 20}\ = 1\), which gave me \(\displaystyle x = 30\). The answer was \(\displaystyle x = 50\) and the equation in the answer key was \(\displaystyle \frac{15}{x - 20}\ + \frac{25}{x}\ = 1\).
Why doesn't my equation work?
2. The graph below represents the graph of y = f(x). Which is the graph of y = f(-x)?
I don't understand why the graph of y = f(-x) is exactly the same as y = f(x).
The graph can be found here: