The answer is 138
Because the angle is 180 and what I did was 2 x 21 = 42 and I did 180-42 equals to 138
Answer:
NOPE, NOT EQUAL!!
Step-by-step explanation:

<h2>
Explanation:</h2>
The commutative property of addition states that:

So applying this property to our expression we have:

<h2>Learn more:</h2>
Evaluating expression: brainly.com/question/14423698#
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Answer:
100
Step-by-step explanation:
100 is the correct answer