Answer:
21
Step-by-step explanation:
I'll represent semi perimeter as s
What we know:
s-A=8
s-B=7
s-C=6
A+B+C=2s
we can substitute all the sides in the equation
s-A=8
s-8-A=0
s-8=A
Do this for B and C
A+B+C=2s
(s-8)+(s-7)+(s-6)=2s
3s-21=2s
-21=-s
s=21
Answer:
Correct options,
a) 
c)
and ∠A = ∠X
Step-by-step explanation:
Given : ΔABC ≅ Δ XYZ
We have choose out of given options that correctly prove that ΔABC ≅ Δ XYZ
Two triangles are said to be similar when their corresponding sides are in same ratio and the measure of their corresponding angles are equal.
That is 
and ∠ A = ∠X , ∠ B = ∠Y AND ∠C = ∠Z
Also ,
We have conditions for two triangle to be similar.
1) SSS : When the ratio of all the three sides of a triangle are equal.
that is 
2) SAS: When the ratio of two corresponding sides are equal and the measure of angle between those sides are equal
and ∠ A = ∠X
Thus, Out of given options,
a) 
c)
and ∠A = ∠X
Answer: 21.4
Step-by-step explanation:
Answer:
3π/2
Step-by-step explanation:
See attached graph
936 squares units I believe.