complementary angles
https://www.aplustopper.com/selina-icse-solutions-class-9-maths-complementary-angles/
https://goo.gl/ZMiiC3
https://sites.google.com/site/aplustoppernotes/complementary-angles
https://goo.gl/jLgPZD
http://cbsetuts.blogspot.in/2018/01/complementary-angles.html
https://goo.gl/efkQ5E
https://goo.gl/oNTbiR
https://goo.gl/FxFzF9
Solution 1(i):
Solution 1(ii):
Solution 1(iii):
Solution 1(iv):
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