Answer:
b. 224
Step-by-step explanation:
We have that to find our 
level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Ztable as such z has a pvalue of 
.
So it is z with a pvalue of 
, so 
Now, find the margin of error M as such
In which 
is the standard deviation of the population and n is the size of the sample.
In this problem:
We want to find n, when 
So
The nearest integer number to 223.9 is 224.
So the correct answer is:
b. 224
Answer:
x= 1.5, y= 3.5
or x= -5, y= 10
Step-by-step explanation:
Let's solve by substitution.
Label the two equations:
y= 2x² +6x -10 -----(1)
y= -x +5 -----(2)
Substitute (2) into (1):
2x² +6x -10= -x +5
2x² +6x +x -10 -5= 0
Simplify:
2x² +7x -15= 0
Factorise:
(2x -3)(x +5)= 0
2x -3= 0 or x +5= 0
2x= 3 or x= -5
x= 1.5
Now that we have found the value of x, we can find the value of y through substitution.
Substitute into (2):
y= -1.5 +5 or y= -(-5) +5
y= 3.5 or y= 10
Supplementary:
Do check out the following should you wish to learn more about solving quadratic equations!
Answer:
A y < -1/2
Step-by-step explanation:
4/3 < -8/3 y
Multiply both sides by 3
3×4/3 < 3× -8/3 y
4 < - 8y
Divide both sides by -8
4/-8 > -8y/-8
The inequality sign changes by dividing by negative
-1/2 > y is same as y < -1/2
Therefore
y < -1/2
I hope this was helpful, please mark as brainliest
they are the same. they are = (equal)
Y = 2
y/4 + 2/3 = y/3 + 1/2
2/4 = 1/2
2/3 = 2/3
2/4 + 2/3 = 2/3 + 1/2
