Number Line:
Closed Circles are used when signs are "≤" or "≥"
Open Circles are used when signs are "<" or ">"
The graph of x > -1 on a number line would be towards the right from -1 with open circle as the sign is ">"
Graph should look like this:
Answer:
The sum of x and y is a rational number
Step-by-step explanation:
X+Y or 5+7=12
A rational number is any number that can be divided without going on and on forever.
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Answer with explanation</u>
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Let
be the average life of light bulbs.
As per given , we have
Null hypothesis : 
Alternative hypothesis : 
Since
is right-tailed and population standard deviation is also known, so we perform right-tailed z-test.
Formula for Test statistic : 
where, n= sample size
= sample mean
= Population mean
=population standard deviation
For
, we have

Using z-value table , Critical one-tailed test value for 0.06 significance level :

Decision : Since critical z value (1.5548) < test statistic (1.6180), so we reject the null hypothesis .
[We reject the null hypothesis when critical value is less than the test statistic value .]
Conclusion : We have enough evidence at 0.06 significance level to support the claim that the new filament yields a longer bulb life
Answer:

Step-by-step explanation:
Look at the picture.
The formula of an area of a triangle:

<em>b</em><em> - base</em>
<em>h</em><em> - height</em>
<em />
We need a length of a height.
Use the Pythagorean theorem:

We have:

Substitute:

<em>subtract 25 from both sides</em>

Calculate the area:

Anything times 1 is equal to itself. Anything times less than one is less than itself. Anything times greater than one is greater than itself. Therefore, 125 times .9, which is less than one, is less than 125