Question 221452
If the measure of an angle is 78 less than the measure of its complement, what is the measure of the angle?  


Would it be x-78=90?


Not quite but you are on the right track...here's one approach.


Step 1.  Complementary angles means two angles add up to 90 degrees.


Step 2.  Let x be the angle.


Step 3.  Let 90-x be its complement.


Step 4  x=90-x-78 since the measure of the angle x is 78 less than its complement (90-x).


Step 5.  Solving equation in Step 4 yields x=12-x or 2x=12.  Then x=6 after dividing by 2.   Its complement is 90-x=84 degrees which is 78 degrees less than the complement of 84.


Step 6.  ANSWER:  The angle is 6 degrees and its complement is 84 degrees.


I hope the above steps were helpful.


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Good luck in your studies!


Respectfully,
Dr J