Question

In the given figure, $\angle \;1$ and $∠ \;2$ are supplementary angles.
If $∠\;1$ is decreased, what changes should take place in $∠\;2$ so that both the angles still remain supplementary?

Answer 1

if $∠\;1$ is decreased then, $∠\;2$ will increase with the same measure, so that both the angles still remain supplementary.

Read more: Supplementary and Complementary Angles