In two supplementary angles, let one angle be ‘x’.
another angle be ‘y’
Sum of these = 180°
∴ x + y = 180 ………… (i)
The larger of two supplementary angles exceeds the smaller by 18 degrees.
∴ x-y = 18 ………… (ii)
From eqn. (ii), x – y = 18
x = 18 + y
Substituting the value of ‘x’ in eqn. (i),
x + y = 180 .
18 +y + y = 180
18 + 2y = 180
2y = 180 – 18
2y = 162
∴ y = \(\frac{162}{2}\)
∴ y = 81
Substituting the value of y’ in x = 18 + y
x = 18 + 81
x = 99
∴ x = 99°, y = 81°.