Step-by-step explanation:
dear by changing the sign by elimination method everything gets cancelled
Answer:
The solution of system of equation is (-2,0)
Step-by-step explanation:
Given system of equation are
Equation 1 : 2x+y=(-4)
Equation 2 : y+
x=(-1)
To plot the equation of line, we need at least two points
For Equation 1 : 2x+y=(-4)
Let x=0
2x+y=(-4)
2(0)+y=(-4)
y=(-4)
Let x=1
2x+y=(-4)
2(1)+y=(-4)
y=(-6)
Therefore,
The required points for equation is (0,-4) and (1,-6)
For Equation 2 : y+
x=(-1)
Let x=0
y+
x=(-1)
y+
(0)=(-1)
y=(-1)
Let x=2
y+
x=(-1)
y+
(2)=(-1)
y=(-2)
The required points for equation is (0,-1) and (2,-2)
Now, plot the graph using this points
From the graph,
The red line is equation 1 and blue line is equation 2
Since. The point of intersection is solution of system of equations
The solution of system of equation is (-2,0)
Form the confidence level (99%), we calculate the "alpha" value
alpha=1-(99/100)=0.01
Now, calculate the critical probability (p-start)
p*=1-(alpha/2)=1-(0.01/2)=0.995
z-score could be calculated from p*,,,
z-score=2.57583
Now, calculate the Margin of Error:
standard deviation = s
number of adults = n
ME=(z*s)/(sqrt n)=(2.57583*12)/(sqrt 250) = 1.955
The confidence interval = mean +or- ME
= 70+1.955 or 70-1.955
So that we can conclude that the 99% confidence interval for the mean beats per minute is 68.045 and 71.955
I hope you got the idea!
Answer:
b. Null: The population average VDAS score for early birds is the same as the population average VDAS score for night owls.
Alt: The population average VDAS scores are different for the two groups.
Step-by-step explanation:
Given
The above data
Required
Determine the null and alternate hypothesis
When looking out for the null hypothesis, only options with equality statements or equal sign should be selected as the null hypothesis.
i.e. statements like "equal to", "the same as", etc.
The alternate hypothesis will then contain inequalities or inequality statements
<em>From the list of options, only option (b) is correct.</em>