Answer with Step-by-step explanation:
Let A is non-singular

We have to prove that
is unique.
Suppose B and C are inverse of A such that
and AC=I
By using property 




Hence, the inverse of A is unique.
Use the substitution method:
2x - 6y = -12
x - 2y = -8
Then x = 2y - 8
Substitute in the first equation:
2(2y - 8) - 6y = -12
4y - 16 - 6y = -12
-2y = 4
y = -2
Now substitute y in one of the two equations given you prefer:
For example x-2*(-2) = -8
x + 4 = -8
x = -12
The solutions are x = -12 and y = -2
X=5
is the answer/................
Solution: We are given:
μ=3.1,σ=0.5,n=50
We have to find P(Mean <2.9)
We need to first find the z score
z= (xbar-μ)/(σ/sqrt(n))
=(2.9-3.1)/(0.5/sqrt(50))
=(-0.2)/0.0707
=-2.83
Now we have to find P(z<-2.83)
Using the standard normal table, we have:
P(z<-2.83)=0.0023
Therefore the probability of the sample mean being less the 2.9 inches is 0.0023