Find DF
Segment addition

mDF = 18

Step-by-step explanation:

DE and EF must add up to DF.

Step 1: Set up equation

mDE + mEF = mDF

x + 7 + 7 = 4x + 2

Step 2: Solve for x

Step 3: Find mDF

mDF = 4x + 2

mDF = 4(4) + 2

mDF = 16 + 2

mDF = 18

since your problem is x^4 = 81, what you have to undeo is the "to the fourth power" part.

the inverse (opposite operation) of "to the fourth power" is "to the fourth root".

  (x^4) ^ ¼   = 81 ^ ¼  

  81 = 3^4     so (3 ^ 4) ^ ¼   =   3 ^ 1   = 3

by hand: (3 ^ 4) ^ ¼   =   3 ^ (4 x ¼) = 3 ^ 1   = 3   (when you take a power to a power, multiply the exponents.)

or, do it by calculator. one way of finding the fourth root is to use ^ (1/4)

step-by-step explanation:

the answer is 54 sq. ft. i just did this question, on odyssey ware, and it was right. make brainliest.