Eric Nicholas K's answer to LZmath's Secondary 2 Maths Singapore question.

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Eric Nicholas K
Eric Nicholas K's answer
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Eric Nicholas K
Eric Nicholas K
2 months ago
Part (a) reason is the sum of angles on a line is 180 degrees.

Part (b) reason is the congruency.

Part (c) reason is the sum of angles in a quadrilateral is 360 degrees.