please help will give BRAINLIEST BRAINLIEST BRAINLIEST BRAINLIEST BRAINLIEST BRAINLIEST BRAINLIEST BRAINLIEST BRAINLIEST BRAINLIEST BRAINLIEST BRAINLIEST for correct answer!!!!!!!!!!!!!

please help will give BRAINLIEST BRAINLIEST BRAINLIEST BRAINLIEST BRAINLIEST BRAINLIEST BRAINLIEST BRAINLIEST BRAINLIEST BRAINLIEST BRAINLIEST BRAINLIEST for co class=

Respuesta :

Answer:

20

Step-by-step explanation:

Since both triangles are similar, then the ratio is 18:6, which is 3:1

Triangle ABC is 3 times the size of DEC.

So, 1/3 of 30 is 10, and 30-10 is 20.

20

it just is i did the math but i’m terrible at explaining