Answer:
y = 81°
Step-by-step explanation:
let the 5 th angle in the pentagon be x
The sum of the interior angles of a polygon is
sum = 180° (n - 2) ← n is the number of sides
Here n = 5, then
sum = 180° × 3 = 540°
sum the angles and equate to 540
x + 95 + 125 + 116 + 105 = 540
x + 441 = 540 ( subtract 441 from 540 )
x = 99°
x and y are adjacent angles and supplementary, sum to 180° , that is
x + y = 180°
99° + y = 180° ( subtract 99° from both sides )
y = 81°
