Answer:
68
Explanation:
The shape is 5 sides polygon.
Sum of interior angles of a 5 sided polygon = 540,
7x + 4 + 8x + 3 + 4x + 8 + 10x - 4 + 6x + 4 = 540
7x + 8x + 4x + 10x + 6x + 4 + 3 + 8 + 4 - 4 = 540
35x + 4 + 3 + 8 = 540
35x + 15 = 540
35x = 540 - 15
35x = 525
Divide 35 on both sides,
x = 525 / 35
x = 15
Angle R = 4x + 18
Substitute the value of x,
Angle R = 4 ( 15 ) + 8
= 60 + 8
Angle R = 68