Does the length of a side of a regular polygon affect the sum of the interior angle measures

20 solve 2(4 x + 3) < 5 x + 21. a) { x | x < 9} b) { x | x > -5} c) { x | x > -9} d) { x | x < 5}

The difference between two numbers is one. three times the larger number minus two times the smaller number is 9. what are the two numbers

What is the name of a polygon that has four congruent sides and theses angle measures 60,120,60,120?