♥️♥️♥️♥️♥️♥️♥️♥️♥️♥️♥️♥️♥️♥️
[tex]124 + c = 180[/tex]
Because they make a straight line.
Subtract sides 124
[tex] - 124 + 124 + c = 180 - 124[/tex]
[tex]c = 56[/tex]
Done...