Answer:
P=41.72
Step-by-step explanation:
S=ACxDB/2
81.7=8.6xDB/2
81.7=4.3xDB|:4.3
19(mm)=DB
DO=19/2=9.5
OC=8.6/2=4.3
(O is the center of the rhombus, where two diagonals meet)
a²+b²=c² (DO²+OC²=DC²)
9.5²+4.3²=c²
90.25+18,49=c²
√108,74=√c²
c≈10.43
P=4c
P=4x10.43
P=41.72
Hope it helps:)
Final Answer: 
Steps/Equations:
Question: 
Step 1: Move the negative sign to the left side.

Step 2: Multiply both sides by
.

Step 3: Simplify
to
.

Step 4: Multiply both sides by
.

~I hope I helped :)~
Answer:
It equals a negative number because there's a negative and a positive which will result in a negative answer
Step-by-step explanation:
if there's a negative and a positive the result will be negative
if it's two negative result would be positive :
-1 × -1 = +1
-1 × +1 = -1
+1 × +1 = +1
-1 × -1 × -1 = -1
-1 × -1 × +1 = +1
Answer:
A: x = 20
Step-by-step explanation: