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2 years ago

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The expression 40x2 – 65x + 50 represents the sum of the interior angles of a regular pentagon in degrees. If the interior angle

s of the pentagon are equal, which expression represents the measure of two angles?
2x2(20 – 32x + 25x2)
2(8x2 – 13x +10)
5x2(8x2 – 13x + 10)
5(3x2 – 8x + 5)

2 answers:

Lunna [17]2 years ago

6 0

The internal angles of a regular pentagon add up to 540 degrrees so two of the angles add up to 2/5 * 540 = 216 degrees
so we multiply the given expression by 2/5 to get the answer.
(
(40x^2 - 65x + 50) * 2/5

= 16x^2 - 26x + 20)

= 2(8x^2 - 13x + 10) which is choice B.

dimaraw [331]2 years ago

5 0

Answer: Second option is correct.

Step-by-step explanation:

Since we have given that

There is a regular pentagon which has 5 equal sides.

And sum of interior angles of a regular pentagon is represented as

$40x^2-65x+50$

As we know the sum of all interior angles of regular pentagon is given by

$(n-2)\times 180^\circ$

where, n is the number of sides.

So, Sum of all interior angles of regular pentagon is $(5-2)\times 180^\circ=3\times 180^\circ=540^\circ$

But we want to represent the measure of two angles.

So, $\frac{2}{5}$ of sum of interior angles.

So, it becomes,

$\frac{2}{5}(40x^2-65x+50})\\\\=2(\frac{40}{5}x^2-\frac{65}{5}x+\frac{50}{5})\\\\=2(8x^2-13x+10)$

Hence, Second option is correct.

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Step-by-step explanation:

Hi!

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Answer:

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Step-by-step explanation:

Data given and notation

n=25 represent the random sample taken

$\hat p=0.2$ estimated proportion

$p_o=0.16$ is the value that we want to test

$\alpha$ represent the significance level

z would represent the statistic (variable of interest)

$p_v$ represent the p value (variable of interest)

Concepts and formulas to use

We need to conduct a hypothesis in order to test the claim that the true proportion of employess are late to work is 0.16, so we need to apply a one sample proportion test:

Null hypothesis: $p=0.16$

Alternative hypothesis: $p \neq 0.16$

When we conduct a proportion test we need to use the z statistic, and the is given by:

$z=\frac{\hat p -p_o}{\sqrt{\frac{p_o (1-p_o)}{n}}}$ (1)

The One-Sample Proportion Test is used to assess whether a population proportion $\hat p$ is significantly different from a hypothesized value $p_o$ .

Calculate the statistic

Since we have all the info requires we can replace in formula (1) like this:

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Statistical decision

It's important to refresh the p value method or p value approach . "This method is about determining "likely" or "unlikely" by determining the probability assuming the null hypothesis were true of observing a more extreme test statistic in the direction of the alternative hypothesis than the one observed". Or in other words is just a method to have an statistical decision to fail to reject or reject the null hypothesis.

The next step would be calculate the p value for this test.

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Answer:

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