Respuesta :

texaschic101
well...it says the sum of the angles measure 360...so lets set them equal to 360

40 + x - 10 + 1/3x + x - 20 = 360...combine like terms
2 1/3x + 10 = 360
7/3x = 360 - 10
7/3x = 350
x = 350/(7/3)
x = 350 * 3/7
x = 1050/7
x = 150 <=====