Respuesta :

Answer:

a) 8

Step-by-step explanation:

a // b and c is transversal

So, alternate exterior angles are congruent.

12x - 12 = 10x + 4

Add 12 to both side

12x = 10x + 4 + 12

12x = 10x + 16

Subtract 10x from both sides

12x - 10x = 16

2x = 16

Divide both sides by 2

x = 16/2

x = 8