https://brilliant.org/practice/complementary-and-supplementary-angles/?p=4

Consider isosceles trapezoid ABCD where m(A) = 80, the m(B) = 100. A and B are supplementary, but they do not make a straight line.

Similarly, in https://brilliant.org/practice/complementary-and-supplementary-angles/?p=4 angle A and B are supplementary, but they don't necessarily make a straight line. In fact, to be a straight line, A and B would have to be the same point. So there isn't enough information to determine.

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Comments

Hi Frank,

In future, if you have an issue with a problem, you can click on the menu to select "Report problem", which will allow the problem creator to respond to you directly.

The phrase "angles form a straight line" does not mean that they currently form a line, but that they can be placed so as to form a straight line. For example, we say that the "angles in a triangle form a straight line", even though none of them meet at the same point.

Calvin Lin Staff - 4 years, 9 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$