For 2 angles to be supplementary, the sum of its measures must be 180.
The supplement angle to 153 is found by substracting 153 to 180.
[tex]\begin{gathered} \measuredangle s+153=180 \\ \measuredangle s=180-153 \\ \measuredangle s=27 \end{gathered}[/tex]The supplement angle to 153 is 27.
