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3 years ago

The sum of a whole number and twice its square is 21. Find the whole number

1 answer:

6 0

SOLUTION:

Let whole number = x

x + 2x^2 = 21

2x^2 + x - 21 = 0

2x^2 + 7x - 6x - 21 = 0

x ( 2x + 7 ) - 3 ( 2x + 7 ) = 0

( 2x + 7 ) ( x - 3 ) = 0

2x + 7 = 0

2x = - 7

x = - 7 / 2

OR

x - 3 = 0

x = 3

ANSWER:

Therefore, as 3 is a whole number while - 7 / 2 isn't a whole number, the whole number must be 3.

Hope this helps! :)
Have a lovely day! <3

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PLEASE ANSWER HURRY THANK YOU

Juliette [100K]

Answer: A. $\dfrac{6}{203}$

Step-by-step explanation:

Given : Jason bought 10 of the 30 raffle tickets for a drawing.

i.e. Total tickets = 30

Also, Number of prizes = 3

The total number of combinations of getting 3 prizes out of 30 tickets = $^{30}C_3$

The number of combinations of getting 3 prizes out of 10 tickets = $^{10}C_3$

Then, the probability that Jason will win all 3 of the prizes if once a raffle ticket wins a prize it is thrown away will be :

$\dfrac{{^{30}C_3}}{^{10}C_3}$

$=\dfrac{\dfrac{10!}{3!7!}}{\dfrac{30!}{3!27!}}=\dfrac{120}{4060}=\dfrac{6}{203}$

Hence, the probability that Jason will win all 3 of the prizes if once a raffle ticket wins a prize it is thrown away is $\dfrac{6}{203}$ .

Hence, the correct answer is A. 6/203.

3 0

3 years ago

Read 2 more answers

2.) Bill sells cleaning products on commission. He earns 40% commission on his sales. If

Karo-lina-s [1.5K]

Answer:

$393.20

Step-by-step explanation:

There are two easy ways to solve this:

1) Use a setup and cross multiply.

First, set up your problem.

$983 100%

$983 is the total amount, so it is equal to 100%. We're trying to find 40% of it, so we can label the amount as $x. Remember, each side has to be in the same type of measurements (i.e. dollars, percentages, inches, etc.).

Then, cross multiply. You should end up with:

100x = 39,320

Then, simplify.

x = 393.2

x = $393.20

2) Convert the percentage to a decimal and multiply.

First, convert the percentage you're looking for into a decimal:

40% × 100 = 0.4

Then, multiply the decimal with the total sales amount:

$983 × 0.4 = 393.2

= $393.20

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3 years ago

a ball is dropped from a height of 6 metres. suppose the ball rebounds 2/3 of the height from which it falls. find total distanc

Aleksandr [31]

Answer:

10 meters.

Step-by-step explanation:

We know the ball travelled a distance of at least 6 meters as that is how far it was dropped.

It rebounded 2/3 of 6 meters, which is 4 meters.

6 meters add 4 meters is 10 meters.

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2 years ago

Draw three lines that are parallel to the x-axis. Read the ordered pairs for points on each line. What generalization can you ma

irina [24]

Answer:

If the line is parallel to the x-axis than only x value changes and y value remains constant.

Step-by-step explanation:

Consider the provided information.

We need to draw three lines that are parallel to the x-axis.

The required graph is shown below:

Now the ordered pairs for points on each line is:

For line y=-3 The ordered pairs are (-1,-3), (0,-3) and (1,-3)

For line y=2 The ordered pairs are (-2,2), (2,2) and (3,2)

For line y=4 The ordered pairs are (-3,4), (0,4) and (4,4)

Here we can observe the x value changes but y values remains constant.

Therefore, if the line is parallel to the x-axis than only x value changes and y value remains constant.

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3 years ago

50 POINTS CORRECT ANSWER ONLY!!

dalvyx [7]

Answer:

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