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3 years ago

6

How many different combinations of two can be made from 80 people?

1 answer:

Alexeev081 [22]3 years ago

3 0

Plugging directly into the combination formula, the answer is $\binom{80}{2}=\frac{80!}{2!78!}=\frac{80\cdot 79}{2\cdot 1}=40\cdot 79=\boxed{3160},$ where we have cancelled out common factors.

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What is the equation of the following graph in vertex form?

Elza [17]

$\bf \boxed{y=(x-{{ h}})^2+{{ k}}}\\\\
x=(y-{{ k}})^2+{{ h}}\qquad\qquad vertex\ ({{ h}},{{ k}})\\\\
-----------------------------\\\\
\textit{vertex is at 4,-4}\implies 
\begin{cases}
h=4\\
k=-4
\end{cases}\implies y=(x-4)^2+(-4)
\\\\\\
\boxed{y=(x-4)^2-4}$

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3 years ago

Read 2 more answers

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andre [41]

Answer:

Option A is correct.

Step-by-step explanation:

If Δ YES ∼ Δ NOT, then it means that ΔYES and ΔNOT are similar triangles.

The similar triangles means that all the corresponding angles of the two triangles are same i.e. ∠ Y = ∠ N, ∠ E = ∠ O and ∠ S = ∠ T

Therefore, according to the property of similar triangles we can write that

$\frac{NO}{YE} = \frac{OT}{ES} = \frac{NT}{YS}$ .

Therefore, option A is correct.

8 0

3 years ago

X= degrees 32° x x

Alla [95]

Answer:

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32+2x=180

2x=180-32

2x=148

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Therefore,X=74

7 0

2 years ago

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Find the area of <br> A triangle with a base of 8 units and a height of 13 units

daser333 [38]

Answer:

52 units squared

Step-by-step explanation:

$13 \: units\: \times 8 \: units \div 2$

7 0

3 years ago

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Over [174]

Answer:

A) Factor

Step-by-step explanation:

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3 years ago