Respuesta :

17 = -13 - 8x .....add 13 to both sides
13 + 17 = -8x
30 = -8x...now divide both sides by -8
-30/8 = x...reduce
- 15/4 or -3 3/4 = x <===
Bring all the like terms together. 

8x is one term without any other term with x in it. 
17 and 13 are terms which are similar because they are real 

17+13=-8x 
30=-8x
30/-8=x 
-3.75=x 

Hope I helped :)