The exterior angles of a heptagon are x, 2x + 5, 3x + 15, 7x – 5, 8x – 10, 6x – 20 and 3x. Find the value of x.
Also find the measure of each of its exterior & interior angle.
Answers
Answer:
As given below
Step-by-step explanation:
Given data exterior angles of a heptagon are
x°, (2x+5)°, (3x+15)°, (7x-5)°, (8x -10)°, (6x - 20)°, (3x)°
⇒ We know that heptagon has 7 sides
⇒ sum of the exterior angles in a polygon = 360°
⇒ x+ 2x + 5 + 3x + 15 + 7x - 5 + 8x -10 +6x -20 + 3x = 360°
⇒ 30x + 15 - 30 = 360°
⇒ 30x -15 = 360°
⇒ 30 x = 375
⇒ 6 x = 75
⇒ x = 12.5
⇒ exterior angles are
⇒ x = 12.5° ,
⇒ 2x + 5 = 2(12.5) +5 = 25 + 5 =30°
⇒ 3x + 15 = 3(12.5) +15 = 37.5 +15 =52.5°
⇒ 7x -5 = 7 (12.5) - 5 = 87.5 -5 = 82.5°
⇒ 8x -10 = 8(12.5) - 10 = 100 - 10 = 90°
⇒ 6x -20 = 6(12.5) -20 = 75 -20 = 55°
⇒ 3x = 3 (12.5) = 37.5°
⇒ interior angles are
⇒ in a polygon exterior angle + interior angle = 180°
⇒ interior angle = 180° - exterior angle
⇒ interior angles at given exterior angles
at 12.5° = 180° - 12.5° = 167.5°
at 30° = 180° - 30° = 150°
at 52.5° = 180° - 52.5° = 127.5°
at 82.5° = 180° - 82.5° = 97.5°
at 90° = 180° - 90° = 90°
at 55° = 180° - 55° = 125°
at 37.5° = 180° - 37.5° = 142.5°