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Elanso [62]
3 years ago
7

At a party, everyone shook hands with everybody else. There were 66 handshakes in total. How many people were at the party?

Mathematics
2 answers:
Zanzabum3 years ago
4 0
12 people were at the party.

You can choose 12 people to be one person, and 11 to be a person they are shaking hands with.  However, this allows us to choose person A, then person B, or Person B, then Person A.  We don't want to double-count this case, so we divide by 2.  12*11/2=66, so 12 works.
olga55 [171]3 years ago
3 0
At a party, everyone shook hands with everybody else. There were 66 handshakes in total. How many people were at the party?12 people. 
Hope i helped, and good luck!
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A right triangle has a hypotenuse length of 12, and one side length of 9. find the missing side length. do the side lengths form
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Use the Pythagorean theorem:

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b^2=63\to b=\sqrt{63}\\\\b=\sqrt{9\cdot7}\\\\b=\sqrt9\cdot\sqrt7\\\\ \boxed{b=3\sqrt{7}}

A Pythagorean triple consists of three positive integers a, b and c, such that

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<h3>The sides of the triangle do not form a pythagorean triple.</h3>
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Nana76 [90]

<em>4℉.</em>

What we know about Degrees is that there is a<em> </em><u><em>Positive</em></u> type and a <u><em>negative</em></u> type.

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If the temperature was -4℉ at 7AM, then it is negative. If it goes up by an amount that is more than 4 then that negative will go up to a positive temperature. In this case: At 9AM it was 8° <u><em>warmer</em></u>.

<u><em>Warmer</em></u><em> is a </em><u><em>keyword</em></u><u>.</u> If it is warmer by an amount, Negative temperatures <u><em>will go up to a positive</em></u> and positive temperature <u><em>will just go up</em></u>. If it gets cooler, negative temperatures <u><em>will go down further</em></u> and positive temperatures <u><em>will go down to a negative</em></u>.

So lets work out this problem with our newfound knowledge.

-4° F at 7AM

8°  warmer at 9AM

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<em>The temperature was 4°  at 9AM.</em>

-Snooky

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The question is an illustration of related rates.

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I added an attachment to illustrate the given parameters.

The representations on the attachment are:

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Read more about related rates at:

brainly.com/question/16981791

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