Step-by-step explanation:
well,
(y - 7)² = (y - 7)(y - 7)
remember how to multiply 2 expressions ?
you have to multiply every term of one expression with every term of the other expression and sum the results all up (incl. considering their individual signs, of course).
so, when we do the multiplication, we get
(y - 7)(y - 7) = y×y - 7×y - 7×y + (-7)×(-7) =
= y² - 14y + 49
and that is clearly different to y² - 49
FYI
y² - 49 is the result of
(y - 7)(y + 7)
because
y×y + 7×y - 7×y + (-7)(7) = y² - 49
Answer:
154.8
Step-by-step explanation:
20% is equal to 20/100= 0.20. So, 0.20 multiplied by 129 will give you 20% of 129 which is 25.8. If Alan ran 20% more then you add 25.8 to 129 which gives you an answer of 154.8.
Equation: 20/100= 0.2
0.2* 129= 25.8
25.8+129= 154.8
Alan ran 154.8 laps.
Answer
Step-by-step explanation:
The answer would be y=-x-3. 3x+3y=-9 is in standard form and you want it to be in y=mx=b form (slope-int) so subtract 3x by both sides. Now, you have 3y=-3x-9. Divide 3 to both sides, now you will get y=-x-3.
If it is parallel, it means the slope is the same. We can convert 4x-y=6 into 4x-6=y after we isolate the x. We can also convert these other equations into slope intercept form. The answers are C, D, and F.
Answer:
When we compare the significance level 
we see that 
so we can reject the null hypothesis at 10% of significance. So the the true mean is difference from 21 at this significance level.
Step-by-step explanation:
Data given and notation
represent the sample mean
represent the population standard deviation
sample size
represent the value that we want to test
represent the significance level for the hypothesis test.
z would represent the statistic (variable of interest)
represent the p value for the test (variable of interest)
State the null and alternative hypotheses.
We need to conduct a hypothesis in order to check if the average age of the evening students is significantly different from 21, the system of hypothesis would be:
Null hypothesis:
Alternative hypothesis:
The statistic is given by:
(1)
Calculate the statistic
We can replace in formula (1) the info given like this:
P-value
Since is a two sided test the p value would be:
Conclusion
When we compare the significance level we see that so we can reject the null hypothesis at 10% of significance. So the the true mean is difference from 21 at this significance level.
