The larger of the two supplementary angles exceeds the smaller by 18°. Find them.
Let the bigger supplementary angle be x° .
and smaller supplementary angle be y° .
According to question -
x° + y° = 180°.....(1)
[∵ properties of supplementary angles ]
and,
x° - y° = 18°.....(2)
Adding equations (1) and (2), we get -
x° = 99°
Substituting the value of x° in equation (1), we get -
y° = 81°
Thus , the two supplementary angles are 81° and 99°.