Answer:
(2, - 3 )
Step-by-step explanation:
Given the 2 equations
2x - 3y = 13 → (1)
x + 2y = - 4 → (2)
Rearrange (2) expressing x in terms of y by subtracting 2y from both sides
x = - 4 - 2y → (3)
Substitute x = - 4 - 2y into (1)
2(- 4 - 2y) - 3y = 13 ← distribute and simplify left side
- 8 - 4y - 3y = 13
- 8 - 7y = 13 ( add 8 to both sides )
- 7y = 21 ( divide both sides by - 7 )
y = - 3
Substitute y = - 3 into (3) for corresponding value of x
x = - 4 - 2(- 3) = - 4 + 6 = 2
Solution is (2, - 3 )
Answer:
1. z = -1.91429
The z score tells us that the head circumference of the girl with the down syndrome ( 44.5 cm) is 1.91429 standard deviations below the mean or average head circumference
2. 2.7792%
Step-by-step explanation:
1. Relative to the WHO data, what is this girls z-score?
z score formula is:
z = (x-μ)/σ, where
x is the raw score = 44.5 cm
μ is the population mean = 47.18cm
σ is the population standard deviation = 1.40cm
z = 44.5 - 47.18/1.40
z = -1.91429
What does the z score tell us?
The z score tells us that the head circumference of the girl with the down syndrome ( 44.5 cm) is 1.91429 standard deviations below the mean or average head circumference
2. Using the WHO data in a normal model, what percentage of the girls has a head circumference that is smaller than the girl with Down's Syndrome?
z score = -1.91429
Probability value from Z-Table:
P(z =-1.91429) = P(x<44.5) = 0.027792
Converting to percentage = 0.027792 × 100
= 2.7792%
The volume of the shaded region is 1650 cubic feet.
B!
hope this helps, it just seems like the best answe.
Write down y=f(x) and then solve the equation for x, giving something of the form x=g(y).
Find the domain of g(y), and this will be the range of f(x). ...
If you can't seem to solve for x, then try graphing the function to find the range.
