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2 years ago

Solve the equation using mental math.

Mathematics

2 answers:

Umnica [9.8K]2 years ago

4 0

I guess answer should be C

ki77a [65]2 years ago

3 0

Answer is C. 3 start fraction 5 over 7 end fraction.

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Simplify this equation Thanks a lot!!!

den301095 [7]

Answer:

-1

Step-by-step explanation:

We need to simplify the given expression . The given expression is ,

$\rm\implies ( 2 \sqrt6 +5)^{2n-1} ( 2\sqrt6 - 5)^{2n-1}$

Here we can see that the power of the both exponent is same that is (2n+1) . Recall the property of exponents ,

$\bf\implies a^m \times b^m = (ab)^m$

Using this property , we have ,

$\rm\implies ( 2 \sqrt6 +5)^{2n-1} ( 2\sqrt6 - 5)^{2n-1}$

This can be written as ,

$\rm\implies\{( 2 \sqrt6 +5) ( 2\sqrt6 - 5)\}^{2n-1}$

Simplifying using ( a+b)(a-b) = a² - b² ,

$\rm\implies\{( 2 \sqrt6)^2 -5^2 \}^{2n-1}\\\\\rm\implies ( 24 - 25)^{2n-1}$

Subtracting the numbers inside the brackets ,

$\rm\implies (-1)^{2n - 1 }$

Now we know that every odd number is in the form of 2n -1 , where n is any integer. Therefore , the power is odd .

Since the base is (-1) , for even power it is 1 and for odd power it is -1 . Therefore the final answer is ,

$\rm\implies\boxed{\quad \red{ -1 }\quad }$

Hence the required answer is (-1) .

4 0

3 years ago

W <img src="https://tex.z-dn.net/?f=41%20%5Cdiv%20646%20%3D%20" id="TexFormula1" title="41 \div 646 = " alt="41 \div 646 = "

krek1111 [17]

This is your answer and for the multiplication I gave it to you step by step

3 0

2 years ago

- Ralph is saving money. He already has $50. To make

ElenaW [278]

Answer:

He will need to mow 5 lawns.

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3 years ago

The length of a rectangle is 4 more than twice the width. The perimeter is 74 feet. Find the length and width of the rectangle.

mafiozo [28]

(2*length)+(2*width)=perimeter
length=4+2w
(2(4+2w))+(2(w))=74
74=(8+4w)+(2w)
74=6w+8
66=6w
w=11
length=4+2(11)
l=4+22
l=26

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2 years ago

HELP ASAP! A college campus has a lawn shaped like a circle with a radius, r, of 60 meters. Which is the best approximation of t

astra-53 [7]

Answer:

he answer is 2800, hope this helps!

Step-by-step explanation: :))

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2 years ago