Answer:
8 and 10.
Step-by-step explanation:
I am assuming the difference of 9° is between their interior angles.
The formula for the interior angle of a regular polygon is 180° - 360°/n, where n is the number of sides.
As the number of sides increase, the interior angle increases.
Therefore 180° - 360°/(5x) = 180° - 360°/(4x) + 9°.
180° - 360°/(5x) = 180° - 360°/(4x) + 9°
360°/(4x) = 360°/(5x) + 9°
90°/x = 72°/x + 9x°/x
=> 90° = 72° + 9x°
9x° = 18°
x = 2.
Hence the number of sides of the regular polygons are 8 and 10.
