Respuesta :

mashayete

Answer:

Step-by-step explanation:

I believe this is geometry,

One exterior angle = sum of two opposite interior angles

ABC + DBC = ABD

5x + 4 +(8x-3) = 79

5x +4 + 8x - 3 =79

13x + 4 - 3 =79

13x + 1 = 79

13x = 79-1

13x = 78

x = 78/13

x = 6