i don’t get the question which makes it harder for me to answer
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Answer:
See below:
Step-by-step explanation:
As there doesn't appear to be a full question, I guess you want me to tell you the definition of complementary.
Complementary and Supplementary angles are when angles make up 90 degrees or 180 degrees respectively, the order being:
+ Supplementary Angles are angles that add up to 180 degrees
+ Complementary Angles are angles that add up to 90 degrees.
So in this context, it means that the sum of the degrees of angles 9 and 10 are equal to 90 degrees.
Cheers!