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3 years ago

Quadratic formula of -2x^2+x+8=0

Mathematics

1 answer:

Vikentia [17]3 years ago

6 0

Answer:

x= 1/4 +(-1/4) √65 or x= 1/4 + 1/4 √65

Step-by-step explanation:

x= −b±√b2−4ac /2a

x= −(1)±√(1)2−4(−2)(8) /2(−2)

x= −1±√65 /−4

x= 1/4 +(-1/4) √65 or x= 1/4 + 1/4 √65

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Use a inequality symbol to compare -3x+7 -10-2

abruzzese [7]

Hey there,

Let's remember that a (inequality symbol) is things like (<), (>), (≤),(≥), (≠).

So, I believe that (-3x+7) and (-10-2) are separate. So we will find that out :)

Let's first do (-3x+7). As simplifying this expression here, we take that "x" of for a while and just stick to (-3+7).

-3
+ 7
______
4

Let's bring that "x" back, and the answer would be 4x for a while.

So far, 4x is the answer.
_____________________________________________________________

Now, Let's work on the other side.

We are talking about (<span>-10-2)

-10
- 2
_______
</span> -12

So, by solving the answer to (-10-2), we got -12.

So, let's determine what is greater . . . . .

$What \ is \ greater?$

-12 or 4.

-12 is on the negative side, and the number 4 is positive. This would conclude that 4 is great than -12.

Your correct answer would look like . . .

<span>(-3x+7) > (-10-2)
</span>
I really hope this helps you alot.

~Jurgen

8 0

3 years ago

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Which construction is illustrated above ?

RSB [31]

Answer:

Option 2.

Step-by-step explanation:

You are bisecting angle BAC with pencil and compass.

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3 years ago

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The dimensions of a rectangle can be represented by

Nataliya [291]

Answer:

Its D. h(x) = 15x2 – 41x + 14

Step-by-step explanation:

Got it right on edge.

8 0

3 years ago

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I am really confused on this. It says find the value of x in each triangle.

photoshop1234 [79]

Make an equation - example, two sides are 2x+60-4x+5=180
equal them to 180 because every triangle is equal to 180
when you find x, multiple two times x plus 60,
s x plus 5
thats the only thing i know about it

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3 years ago

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The average maximum monthly temperature in Campinas, Brazil is 29.9 degrees Celsius. The standard deviation in maximum monthly t

kvv77 [185]

Answer:

$P(X>32)=P(\frac{X-\mu}{\sigma}>\frac{32-\mu}{\sigma})=P(Z>\frac{32-29.9}{2.31})=P(z>0.909)$

And we can find this probability with the complement rule and using the normal standard distributon table or excel we got:

$P(z>0.909)=1-P(z$

And if we convert this to a % we got 18.2 % of maximum temperatures higher or equal than 32 C

Step-by-step explanation:

Previous concepts

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".

Solution to the problem

Let X the random variable that represent the maximum monthly temperature of a population, and for this case we know the distribution for X is given by:

$X \sim N(29.9,2.31)$

Where $\mu=29.9$ and $\sigma=2.31$

We are interested on this probability

$P(X>32)$

And the best way to solve this problem is using the normal standard distribution and the z score given by:

$z=\frac{x-\mu}{\sigma}$

If we apply this formula to our probability we got this:

$P(X>32)=P(\frac{X-\mu}{\sigma}>\frac{32-\mu}{\sigma})=P(Z>\frac{32-29.9}{2.31})=P(z>0.909)$

And we can find this probability with the complement rule and using the normal standard distributon table or excel we got:

$P(z>0.909)=1-P(z$

And if we convert this to a % we got 18.2 % of maximum temperatures higher or equal than 32 C

8 0

3 years ago