Use the formula for the sum of the interior angles of a polygon with n sides: Sum of interior angles = (n-2)(180°) Use n=8 Sum of interior angles = (8-2)(180°) = 6(180°) = 1080° (x+55)°+(3x+20)°+4x°+(4x-10)°+(6x-55)°+(3x+52)°+3x° = 1080° x+55+3x+20+4x+4x-10+6x-55+3x+52+3x = 1080 Combine like terms and solve for x. You finish. Edwin