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3 years ago

10

Rationalize the denominator.

1 answer:

mel-nik [20]3 years ago

3 0

Answer:

7sqrt(15) - 5sqrt(6)

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45

Step-by-step explanation:

7 -sqrt(10)

-----------------------

3 sqrt(5) *sqrt(3)

7 -sqrt(10)

-----------------------

3 sqrt(15)

Multiply the top and bottom by sqrt(15)/ sqrt(15)

7 -sqrt(10) sqrt(15)

----------------------- * ------------

3 sqrt(15) sqrt(15)

(7 -sqrt(10))* sqrt(15)

-----------------------------------

3 *15

Distribute

7sqrt(15) - sqrt(150)

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45

sqrt(ab) =sqrt(a) sqrt(b)

150 = 25*6

7sqrt(15) - sqrt(25)sqrt(6)

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45

7sqrt(15) - 5sqrt(6)

------------------------------

45

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4.8
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Step-by-step explanation:

Given:-

Dori walking at 50 steps/min.

Malory walking at 90 steps/min.

Now, as Dori left the house 20 mins ahead of Malory and

Dori is walking at speed of 50 steps/min, that means

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