Answer:
20
Step-by-step explanation:
You do have some idea of how the question is done. It won't take much to learn the right answer.
braces = square root( length^2 + height^2)
braces = √( (12)^2 + (16)^2) )
braces = √(144 + 256)
braces = √(400)
braces = 20
