Answer:
84
Step-by-step explanation:
The sum of the central angles is equal to 360. You set up an equation:
13n - 16 + 7n + 12 + 6n = 360
You combine like terms:
26n - 4 = 360
You add 4:
26n = 364
Divide by 26:
n = 14
To find BC you plug in "n=14" in the equation BC = 6n. You multiply 14 by 6 and get 84
Step-by-step explanation:
Since AB=I, we have
det(A)det(B)=det(AB)=det(I)=1.
This implies that the determinants det(A) and det(B) are not zero.
Hence A,B are invertible matrices: A−1,B−1 exist.
Now we compute
I=BB−1=BIB−1=B(AB)B−1=BAI=BA.since AB=I
Hence we obtain BA=I.
Since AB=I and BA=I, we conclude that B=A−1.
