Factor out the common terms in the first two terms, then in the last two terms;
3x^2(b - 3x) - (b - 3x)
Factor out the common term b - 3x
<u>= (b - 3x)(3x^2 - 1)</u>
Answer:
any translation can be replaced by a rotation
SOLUTION
The mean is 4min
standard deviation is 1min
the z score is
where
then we have
The probability the call lasted less than 3 min will be
Therefore, the probability that (z < -1 ) is
[tex]\begin{gathered} Pr(z<-1)=Pr(0
Hence, the percentage of the calls that lasted less than 3 min is 16%
Substituting -3 for x, we have: (-3)^2-3*-3-7. This simplifies to 9+9-7, or 11.