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3 years ago

How would you do number 12 and 15?

Mathematics

1 answer:

Gnesinka [82]3 years ago

7 0

Answer:

$x_1=x_2=-\dfrac{2}{3}$

Step-by-step explanation:

For the quadratic equation $ax^2+bx+c=0$ the discriminant is defined as

$D=b^2-4ac$

and the quadratic formula for the roots gives us two roots:

$x_1=\dfrac{-b-\sqrt{D}}{2a}$

and

$x_2=\dfrac{-b+\sqrt{D}}{2a}$

For the equation $9x^2 +12x+4=0$ use quadratic formula to find roots:

$D=12^2-4\cdot 9\cdot 4=144-144=0$

So,

$x_1=x_2=\dfrac{-12\pm \sqrt{0}}{2\cdot 9}=-\dfrac{12}{18}=-\dfrac{2}{3}$

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Norma-Jean [14]

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This is always true.
The definition of 'absolute' value is 'size of the number without its sign'.
That's what this expression says.

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3 years ago

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Komok [63]

Answer: Correct critical value = 2.2622

Step-by-step explanation:

Confidence interval for population mean when population standard deviation is unknown:

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So, the 95 percent confidence interval estimate for the mean :

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3 years ago

PLEASE HELP!!!!! explain too please

ale4655 [162]

Answer:

8. Not similar

9. Similar

Step-by-step explanation:

8. You could try to us the AA theorem which means that two angles in the triangle are equal, which would mean that the triangles are similar. But 46+58=104 and 180-104=76 so there are not two similar angled between the triangles.

9. You can use the same theorem for this problem (AA). So 106+31=137 and then 180-137=43 which is one of the angles in the second triangle. Since at least two of the angles are equal, you can use AA theorem yo prove they are similar.

Hope this helps!

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3 years ago

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. Find the value of $1,300 invested at 4.2% interest compounded continuously for 5 years, 9 months. Round your final answer to t

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3 years ago

Someone help me with this math PlZZ!!!imma use 80 points!!

LiRa [457]

Answer:

Will you try to please repost it so i can better answer it and try to reword it some because it's a bit confusing for those who want to help me

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3 years ago

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