Question

Polygon Angle Sums - Part 2

Answer 1

Answer:

x = 80°

Step-by-step explanation:

Find attached the complete question with diagram. Also find attached the diagram used for solving the question.

There area 3 angles in the diagram:

x + 8, 2x + 12, x + 20

Let the interior angles be labelled a, b, and c

a+ 2x+12 = 180° (sum of angles on a straight line)

a= 180-(2x+12) = 168 -2x in degrees

b+ x+20 = 180° (sum of angles on a straight line)

b = 180-(x+20) = 160 -x in degrees

c+ x+8 = 180° (sum of angles on a straight line)

c = 180-(x+8) = 172-x in degrees

a+b+c = 180° (sum of angles in triangle)

(168 -2x)° + (160 -x)° + (172-x)° = 180°

500 -4x = 180

500-180 = 4x

320 = 4x

x = 320/4

x = 80°