3 years ago

Find the value of the combination. 21 C 3 7,980 2,660 1,330

1 answer:

4 0

To evaluate the combination we proceed as follows:
21C3
Given nCk we shall have:
n!/[(n-k)!k!]
thus plugging the values in the expression we get:
21!/[(21-3)!3!]
=21!/(18!×3!)
=1330
Answer: 1330

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14 units is the answer :)

Step-by-step explanation:

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earnstyle [38]

Answer:

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Step-by-step explanation:

Sum of 3 angles in a triangle is 180..

The angles given are:

7x + 12

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Also, straight angle is 180 degrees, thus Angle 1 and (14x + 9) angle is sum to 180, thus we can write:

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Or we can write this as:

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We substitute this expression for Angle 1 into 1st equation we got and solve for x first,

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Hence Angle 1 would be:

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6 0

2 years ago

Find the valid value(s) for x:<br> x2 +5x+6<br> = 1<br> x+3

-BARSIC- [3]

Answer:

x=-1

Step-by-step explanation:

x+3≠0

x≠-3

x²+5x+6=x+3

x²+5x+6-x-3=0

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3 years ago

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Number 3. I think so.

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sammy [17]

Answer:

3(x−4)(x+2)

Step-by-step explanation:

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3 years ago