Respuesta :

the answer is x=39


all the angles (degrees) should add up to 180 for a triangle.

39 + 102 = 141
180-141= 39


so, 39+39+102=180 :)

Answer:

x=39

Step-by-step explanation:

All sides of triangle must be equal to a grand total of 180°

So, we can take the two sides we know that have the lengths,

(39°, 102°)

39+102=141°

Now we can subtract 180° by 141° to get 39°.

x = 39°