Perform each calculation. See Example 3. ...

Question

Perform each calculation. See Example 3.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              90° ― 36° 18' 47"

Accepted Answer

Hello, everyone. We are asked to subtract the angles. 74 degrees minus 44 degrees. 15 minutes, 54 seconds. Our answer choices are a 29 degrees. 44 minutes. Six seconds. B 29 degrees. 16 minutes, six seconds. C 28 degrees. 45 minutes. 54 seconds. D 28 degrees. 44 minutes. 54 seconds first, I'm gonna rewrite this so that I have the degrees directly over the degrees and the minutes directly over the minutes, the seconds directly over the seconds. So we'll have 74 degrees minus degrees. 15 minutes, 54 seconds. Notice that 74 degrees doesn't have any minutes or seconds listed. I'm gonna fill those in as zeros for the time being just so I can see the placeholders. Now, think back to when you learned to subtract and you had to borrow from a previous column to do something like 100 minus 15. That's what we're gonna do here. We're gonna start by recalling that one degree is equal to minutes. So I'm gonna rewrite my top angle as 73 degrees because I'm borrowing one degree and I will rewrite that as 60 minutes. And I still have zero seconds at this point. And I'm just rewriting my second angle exactly as it is. So, 44 degrees, 15 minutes, 40 I'm sorry, 54 seconds. I'm gonna borrow one more time this time. I'm borrowing from the minutes to fill in the seconds column. So also recall that one minute is equal to seconds. So I'm gonna borrow one from the 60 minutes. So we'll have 73 degrees, 59 minutes, 60 seconds. The second angle again is not changing. It is still 44 degrees, 15 minutes, 54 seconds. And we can now subtract them because each column has a value in it. So starting with the seconds, 60 seconds minus 54 seconds is six seconds. 59 minutes minus 15 minutes is 44 minutes and degrees minus 44 degrees is degrees. So once we did all of our borrowing and subtracting, our final answer is 29 degrees, 44 minutes, six seconds, which is answer choice. A have a nice day.

Perform each calculation. See Example 3. 90° ― 36° 18' 47"

Key Concepts

Angle Measurement

Subtraction of Angles

Trigonometric Functions

Watch next