To find invers
1. solve for y
2. replace y with xinverse
so
x=4-4y+y^2
reorder right side
x=y^2-4y+4
factor right side
x=(y-2)^2
squaer root both sides
+/-√x=y-2
add 2 to both sides
2+/-√x=y
switch x and y
2+/-√y=xinverse
xinverse=2+√y or 2-√y
subtract 4 from both sides
Answer:
The reason why standard deviation of the entire class is greater than standard deviation of males and females considered separately, is that mean values for males and females are different from each other.
Step-by-step explanation:
The concept of mean is well represented by the following formula
mean =
, where x1, x2, xn are the observations and N is the number of observations (population).
Standard deviation represents the distance between each observation and the mean of the population (all observations). The formula for this parameter is:
Standard deviation =√[((x1 - x)² + (x2-x)² + ....+ (xn-x)²)/N-1], where x1, x2,..., xn are the observations and x is the mean value.
In this case you have that each height registered is an observation and the number of observations represents the N value. As you can see if the mean for males is different from that of females their standard deviation will be different too. Usually males have heigths greater than that of females (1.77 vs 1.64, in USA for example), and heights inside each group will be more similar than between groups. Then, when you mix all observation there will be an increase in standard deviation, because you are mixing very different heigths
Answer:
z=6+2i maybe
Step-by-step explanation:
Answer:
C. When the equations -10x + 5y = -60 and -3x − 5y = -5 are added together, a third linear equation, -13x = -65, is formed, and it shares a common solution with the original equations.
Step-by-step explanation:
2x-y=12
-3x-5y=-5
multiply the first equation by -5
-10x +5y = -60
add the 2 equations together
-3x-5y=-5
-10x +5y = -60
-------------------------
-13x = -65
We use the addition property of equality which says adding the same thing to both sides, doesn't change the equation, so we will get the same answer as the original equation
Answer:-25
Step-by-step explanation:
simplify