harpazo
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Section R.2
Algebra Essentials
Michael Sullivan
Textbook: College Algebra Edition 9
In other countries, normal household voltage is 220 volts. It is acceptable for the actual voltage x to differ from normal by at most 8 volts. A formula describes this is
|x - 220| ≤ 8
A. Show that a voltage of 214 volts is acceptable.
Solution:
|x - 220| ≤ 8
Let x = 214
|214 - 220| ≤ 8
| 6 | ≤ 8
6 ≤ 8...This is a true statement. I conclude that a voltage of 214 is acceptable.
B. Show that a voltage of 209 is not acceptable.
Solution:
|x - 220| ≤ 8
Let x = 209
|209 - 220| ≤ 8
| - 11 | ≤ 8
11 ≤ 8...This is false statement. I conclude that a voltage of 209 is NOT acceptable.
Do I understand this question correctly?
Algebra Essentials
Michael Sullivan
Textbook: College Algebra Edition 9
In other countries, normal household voltage is 220 volts. It is acceptable for the actual voltage x to differ from normal by at most 8 volts. A formula describes this is
|x - 220| ≤ 8
A. Show that a voltage of 214 volts is acceptable.
Solution:
|x - 220| ≤ 8
Let x = 214
|214 - 220| ≤ 8
| 6 | ≤ 8
6 ≤ 8...This is a true statement. I conclude that a voltage of 214 is acceptable.
B. Show that a voltage of 209 is not acceptable.
Solution:
|x - 220| ≤ 8
Let x = 209
|209 - 220| ≤ 8
| - 11 | ≤ 8
11 ≤ 8...This is false statement. I conclude that a voltage of 209 is NOT acceptable.
Do I understand this question correctly?