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3 years ago

Help me with this!! I dont understand this question

Mathematics

1 answer:

Sonja [21]3 years ago

4 0

Answer:

the answer would be c

Step-by-step explanation: Because the values inside of the parenthesis don't have the same variable, they cannot be combined. Using the 9 on the outside of the parenthesis you would multiply 9 by 3r, which gives you 27r, and 9 by -4 to create -36. The new equation would be 27r - 36, which is equivalent to the equation shown next to it.

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What is 5\18 equal to

Evgesh-ka [11]

The answer is 3.3 hope this helps you .Skateboards

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3 years ago

In a shipment of 56 vials, only 13 do not have hairline cracks. If you randomly select 3 vials from the shipment, in how many wa

Elden [556K]

Answer: 27434

Step-by-step explanation:

Given : Total number of vials = 56

Number of vials that do not have hairline cracks = 13

Then, Number of vials that have hairline cracks =56-13=43

Since , order of selection is not mattering here , so we combinations to find the number of ways.

The number of combinations of m thing r things at a time is given by :-

$^nC_r=\dfrac{n!}{r!(n-r)!}$

Now, the number of ways to select at least one out of 3 vials have a hairline crack will be :-

$^{13}C_2\cdot ^{43}C_{1}+^{13}C_{1}\cdot ^{43}C_{2}+^{13}C_0\cdot ^{43}C_{3}\\\\=\dfrac{13!}{2!(13-2)!}\cdot\dfrac{43!}{1!(42)!}+\dfrac{13!}{1!(12)!}\cdot\dfrac{43!}{2!(41)!}+\dfrac{13!}{0!(13)!}\cdot\dfrac{43!}{3!(40)!}\\\\=\dfrac{13\times12\times11!}{2\times11!}\cdot (43)+(13)\cdot\dfrac{43\times42\times41!}{2\times41!}+(1)\dfrac{43\times42\times41\times40!}{6\times40!}\\\\=3354+11739+12341=27434$

Hence, the required number of ways =27434

5 0

2 years ago

Solve x2 + 14x = -40 by completing the square.

zalisa [80]

Answer: C x=-4 and -10

Step-by-step explanation:

6 0

1 year ago

I need the answer !! Please help!

STALIN [3.7K]

Answer:

Step-by-step explanation:

8x²-x-8

7 0

3 years ago

A rectangular flower bed is five feet longer than it is wide. its area is eighty-four square feet.

777dan777 [17]

Lets say w is the width of the flower bed. We can make an equation to find the area.
The length of the of the flower bed is (w+5) and the width is w.
To find the area we need to multiply the length(w+5) by the width(w) and set it equal to 84,
(w+5)(w)=84
w^2 +5w=84
Using the quadratic equation you get the solutions of 7 and -12. Since 7 is positive it is our width. Our length is 7+5 or 12.

3 0

2 years ago