Answer:
x = -5
y = -5
Step-by-step explanation:
If you multiply the top equation by negative 2, you can add it to the bottom equation and cancel out the x:
-2(-x + 5y = -20) --> 2x - 10y = 40
Add this to the bottom equation top to bottom:
2x - 10y = 40
-2x + 4y = -10
You get:
-6y = 30
Then solve for y:
y = -5
Plug this back in for either equation and solve for x:
-x + 5(-5) = -20
-x -25 = -20
-x = 5
x = -5
Your answers are:
x = -5
y = -5
Answer: (x,y)=(14/4,0)
Step-by-step explanation:
y=-2(x-3)(2)+2
Clear the brackets
y=-2(2x-6)+2
y=-4x+12+2
y=-4x+14
To get the x-intercept y=0
0=-4x+14
4x=14
x=14/4
(x,y)=(14/4,0)
Answer:
y = 2
Step-by-step explanation:
varies inversely
xy = k
y = 7 when x = 2/3
(2/3)7 = k
14/3 = k
k = 14/3
--------------------
find y when x = 7/3
(7/3)y = 14/3
multiply both sides by 3/7
y = 14/3 * 3/7
y = 2
Answer:
For this case the confidence interval is given by :

Step-by-step explanation:
Data provided
represent the sample mean for the fuel efficiencies
population mean
s=2.51 represent the sample standard deviation
n=601 represent the sample size
Confidence interval
The formula for the confidence interval of the true mean is given by:
(1)
The degrees of freedom for this case is given by:
The Confidence level for this case is 0.95 or 95%, and the significance level
and
and the critical value is given by
Replcing into the formula for the confidence interval is given by:
For this case the confidence interval is given by :
