Answer:
B, 
Step-by-step explanation:
Diagonals of a square are congruent so AC= 4
using pythagorean theorem we can then do
=

Then for perimeter we times the
by 4 and get

Hope this helps and please mark brainliest!!
Answer:
80 cm
Step-by-step explanation:
To find the length of both segments together, convert the lengths into one unit measure. Convert 500 mm into centimeters by dividing it by 10. 500/10 = 50 cm. Now add 30 + 50 = 80 cm. The segment is 80 cm long.
7n + 3 = 3n + 27
7n -3n =27-3
4n =24
n= 6.