# PROBLEM solving(complementary and supplementary) guys help!!

• Aug 1st 2010, 06:00 AM
ejaykasai
PROBLEM solving(complementary and supplementary) guys help!!
this is all about the complementary and supplementary angle..
These are the problems I can't solve.. Can anyone explain how to solve this? Advance thanks..

18. If the measure of an angle is (7x-13)degrees and the measure of it's supplement is (5x-11)degrees, find x.

19. Find the measure of the smaller angle of complementary angles, if the measure of the larger angle is (5x+18)degrees and the measure of the smaller angle is half of the larger.

21. Two complementary angles have the difference of 18degrees. Find their measures.
• Aug 1st 2010, 06:22 AM
Dinkydoe
First of all, what is your problem exactly? 2 angles a,b are supplementary angles if a+b=180 degrees. And a,b are complementary if a+b= 90 degrees.
Thus it boils down to basic algebra...

18. solve (7x-13)+(5x-11)= 180 for x

19. Solve (5x+18)+1/2(5x+18)= 90 for x and then find the value (5x+18) by plugging in x

20 .....you can do this one.
• Aug 1st 2010, 06:50 AM
ejaykasai
So the answer in 19 must be a fraction number?
• Aug 1st 2010, 06:55 AM
Dinkydoe
Quote:

So the answer in 19 must be a fraction number?
Why not trying to solve the question first, before asking. Yes, x is a fraction number, but (5x+18) is not!