find the length of MN.

Answer:
32
Step-by-step explanation:
39 = 4(x + 5) + 2x + 1
39 = 4x + 20 + 2x + 1
39 = 6x + 21
18 = 6x
x = 3
MN = 4(x + 5)
MN = 4(3 + 5)
MN = 4(8)
MN = 32
hope this helped!
Step-by-step explanation:
MP = MN + NP
39 = 4(x+5) + 2x+1
39 = 4x + 20 + 2x + 1
39 = 6x + 21
6x = 39-21
6x = 18
x = 3
Then,
MN = 4(3+5)
= 4×8
= 32