Final answer:
To find the length of each side of a regular polygon, equate the given expressions and solve for x. Substitute the value of x back into either expression to find the length of each side.
Step-by-step explanation:
In a regular polygon, all sides are equal in length. In this case, we are given two expressions for the length of each side: 2x + 15 and 5x - 9.
To find the length of each side, we need to equate both expressions and solve for x. So, 2x + 15 = 5x - 9.
Simplifying this equation, we get 24 = 3x, which means x = 8. Substituting this value back into either expression gives us the length of each side: 2(8) + 15 = 31.