Answer:
C) 2
Step-by-step explanation:
step 1: Find mean of data set
2+4+4+5+7+8 = 30
30/6 = 5
Mean = 5
step 2: subtract each data value from the mean and square it
5-2 = 3; 3² = 9
5-4 = 1; 1² = 1
5-4 = 1; 1² = 1
5-5 = 0; 0² = 0
5-7 = -2; (-2²) = 4
5-8 = -3; (-3²) = 9
Add the squared results:
9+1+1+0+4+9 = 24
Divide 24 by 6 to get the Variance of 4
Take the square root of the Variance to get the Standard Deviation
= 2
Answer:
Step-by-step explanation:
Look at the component form of each vector.
Note that vector c is <4,4> and vector d is <-2,-2>
If one imagined the line that contained each vector, the line for both would have a slope of 1, because
Since they have the same slope they are parallel, but since they are in opposite directions, we often call them "anti-parallel" (simply meaning parallel, but in opposite directions).
If two vectors are parallel, one vector can be multiplied by a scalar to result in the other vector. This means that there is some number "k", such that , or equivalently,
and
.
If and
, we just need to substitute known values and solve for k:
Double checking that k works for the y-coordinates as well:
?
So,