Question

Write the measure of the angle that is at vertex Y in the figure below.

Answer 1

∠ Y = 70°

Explanation:

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° × (5 - 2) = 180° × 3 = 540°

sum the 5 angles and equate to 540°

∠ Y + ∠ A + ∠ D + ∠ O + ∠ T = 540° ( substitute values )

∠ Y + 150° + 120° + 90° + 110° = 540°

∠ Y + 470° = 540° ( subtract 470° from both sides )

∠ Y = 70°