Respuesta :

Answer:

x = 45

LNM = 135

Step-by-step explanation:

45 + 3x = 180

45 - 45 + 3x = 180 - 45

3x = 135

3x/3 = 135/3

x = 45

45 x 3 = 135

135 because 180-45=135 and I straight line is 180