Respuesta :

Answer:

f=8

Step-by-step explanation:

Step 1-

All triangles have interior angles equal to 180, so with this knowledge, we can do:

180-40-30=110

Step 2-

Knowing that 110 is equal to S, we set it equal in an equation and solve

(13f+6)=110

Subtract 6 from both sides to get rid of it

13f=104

Divide 104 by 13 to get rid of it

f=8

Hope this helps!