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3 years ago

There are 8 books on a shelf, of which 2 are paperbacks and 6 are hardbacks. how many possible selections of 4 books from this s

helf include at least one paperback?

Mathematics

1 answer:

trapecia [35]3 years ago

8 0

$\displaystyle \binom{6}{3}\cdot2+\binom{6}{2}=\dfrac{6!}{3!3!}\cdot2+\dfrac{6!}{2!4!}=\dfrac{4\cdot5\cdot6}{2\cdot3}\cdot2+\dfrac{5\cdot6}{2}=40+15=55$

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Select a setting so that each given point will lie within the viewing window.

NemiM [27]

Answer:

The given points are

$(-13,3)\\(0,0)\\(-2,-7)$

The setting would have a interval or 2 units above and below the minimum and maximum of each coordinate.

The given maxium horizontal coordinate is 0.

The given minimum horizontal coordinate is -13.

The given maximum vertical coordinate is 3.

The given minimum vertical coordinate is -7.

Now, we extend each maximum and minimum value by 2 units to create the setting.

So, the setting is

$x_{min}=-15\\x_{max}=2\\ y_{min}=-9\\y_{max}=5$

With a scale of 2 units.

6 0

3 years ago

I need help and I’m too lazy to type this out tell me you can’t see the picture

wlad13 [49]

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3 years ago

F(x)=2x^2 -5 , simplify f(x+h)/h , where h≠0

7nadin3 [17]

Answer:

$\huge\boxed{\dfrac{f(x+h)}{h}=\dfrac{2x^2+4xh+2h^2-5}{h}}$

$\huge\boxed{\dfrac{f(x+h)}{h}=\dfrac{2x^2-5}{h}+4x+2h}$

Step-by-step explanation:

$f(x)=2x^2-5\\\\\dfrac{f(x+h)}{h}=\dfrac{2(x+h)^2-5}{h}=\dfrac{2(x^2+2xh+h^2)-5}{h}\\\\\dfrac{f(x+h)}{h}=\dfrac{2x^2+4xh+2h^2-5}{h}\\\\h\neq0$

4 0

2 years ago

Coras kitten weighs 1,200 grams. If he weighed 550 grams at the last visit to the veterans office, what percent is the increase

Juli2301 [7.4K]

First, find the different of the two weights
d = 1,200 - 550
d = 650

The different of the weights is 650

Second, to find the percentage, we should compare the difference to the former weight. So we compare 650 to 1,200, then multiply it to 100%
percentage = 650/1,200 × 100%
percentage = (65,000/1,200) %
percentage = 51.17%
percentage = 51%

The percent of increase is 51%

8 0

3 years ago

A bag contains 6 one-dollar coins and 4 two-dollar coins. Three coins are taken at random without replacement.

IgorLugansk [536]

The answer is b why because I had did it on the test and I had got it right HOPEFULLY IT HELPS

3 0

2 years ago