All categories

2 years ago

The value of polynomial 5x-4x^2+3, when x=-1

Mathematics

1 answer:

Alchen [17]2 years ago

8 0

Answer:

-6

Step-by-step explanation:

$\text{Given that,}\\\\5x-4x^2 +3 \\\\\text{When}~ x = -1,\\\\~~~5(-1) -4(-1)^2 +3 \\\\=-5-4(1)+3\\\\=-5-4+3\\\\=-5-1\\\\=-6$

You might be interested in

A laptop is on sale for 45% off the regular price. If the sale price is $299.75, what was the original price?

Wewaii [24]

The original price of the laptop is calculated as $545

<h3>How to find the original Price?</h3>

We are given;

Sales Price of Laptop = $299.75

Now, the laptop is on sale for 45% off regular price.

If original price is x, then we can express that;

(100% - 45%) * x = 299.75

Thus;

55%x = 299.75

0.55x = 299.75

x = 299.75/0.55

x = $545

Thus, the original price of the laptop is calculated as $545

Read more about Original Price at; brainly.com/question/7459025

#SPJ1

6 0

1 year ago

Find the coefficient of variation for each of the two sets of data, then compare the variation. Round results to one decimal pla

svp [43]

Here is the correct computation of the question given.

Find the coefficient of variation for each of the two sets of data, then compare the variation. Round results to one decimal place. Listed below are the systolic blood pressures (in mm Hg) for a sample of men aged 20-29 and for a sample of men aged 60-69.

Men aged 20-29: 117 122 129 118 131 123

Men aged 60-69: 130 153 141 125 164 139

Group of answer choices

Men aged 20-29: 4.8%

Men aged 60-69: 10.6%

There is substantially more variation in blood pressures of the men aged 60-69.

Men aged 20-29: 4.4%

Men aged 60-69: 8.3%

There is substantially more variation in blood pressures of the men aged 60-69.

Men aged 20-29: 4.6%

Men aged 60-69: 10.2 %

There is substantially more variation in blood pressures of the men aged 60-69.

Men aged 20-29: 7.6%

Men aged 60-69: 4.7%

There is more variation in blood pressures of the men aged 20-29.

Answer:

(c)

Men aged 20-29: 4.6%

Men aged 60-69: 10.2 %

There is substantially more variation in blood pressures of the men aged 60-69.

Step-by-step explanation:

From the given question:

The coefficient of variation can be determined by the relation:

$coefficient \ of \ variation = \dfrac{standard \ deviation}{mean}*100$

We will need to determine the coefficient of variation both men age 20 - 29 and men age 60 -69

To start with;

The coefficient of men age 20 -29

Let's first find the mean and standard deviation before we can do that ;

SO .

Mean = $\dfrac{\sum \limits^{n}_{i-1}x_i}{n}$

Mean = $\frac{117+122+129+118+131+123}{6}$

Mean = $\dfrac{740}{6}$

Mean = 123.33

Standard deviation $= \sqrt{\dfrac{\sum (x_i- \bar x)^2}{(n-1)} }$

Standard deviation = $\sqrt{\dfrac{(117-123.33)^2+(122-123.33)^2+...+(123-123.33)^2}{(6-1)} }$

Standard deviation = $\sqrt{\dfrac{161.3334}{5}}$

Standard deviation = $\sqrt{32.2667}$

Standard deviation = 5.68

The $coefficient \ of \ variation = \dfrac{standard \ deviation}{mean}*100$

$coefficient \ of \ variation = \dfrac{5.68}{123.33}*100$

Coefficient of variation = 4.6% for men age 20 -29

For men age 60-69 now;

Mean = $\dfrac{\sum \limits^{n}_{i-1}x_i}{n}$

Mean = $\frac{ 130 + 153 + 141 + 125 + 164 + 139}{6}$

Mean = $\dfrac{852}{6}$

Mean = 142

Standard deviation $= \sqrt{\dfrac{\sum (x_i- \bar x)^2}{(n-1)} }$

Standard deviation = $\sqrt{\dfrac{(130-142)^2+(153-142)^2+...+(139-142)^2}{(6-1)} }$

Standard deviation = $\sqrt{\dfrac{1048}{5}}$

Standard deviation = $\sqrt{209.6}$

Standard deviation = 14.48

The $coefficient \ of \ variation = \dfrac{standard \ deviation}{mean}*100$

$coefficient \ of \ variation = \dfrac{14.48}{142}*100$

Coefficient of variation = 10.2% for men age 60 - 69

Thus; Option C is correct.

Men aged 20-29: 4.6%

Men aged 60-69: 10.2 %

There is substantially more variation in blood pressures of the men aged 60-69.

4 0

3 years ago

Solve for x.<br> 6x + 5 = -x + 40<br> B. x= -5<br> A. x = -9<br> D. x= 9<br> C. x = 5

denis23 [38]

C, x=-5, hope this helps

3 0

3 years ago

Tessa buy candy that cost $4 per pound. she will spend more than $40 on candy. what are the possible number of pounds she will b

ivanzaharov [21]

Answer:

She will buy at least 10 pounds or more.

Step-by-step explanation:

If each pound costs $4 and she is spending $40 worth, she needs to buy 10 pounds in order to spend the minimum of $40. She can buy more than 10 pounds to keep spending more money. 11, 12, 13, 14, 15, and so forth are all possible numbers in pounds she will buy.

5 0

3 years ago

Which pair of angles in the figure creates a straight angle

mestny [16]

im assuming i just pick two angles cause i cant see the options? two 90 degree angles.

and my name is teagan too :D

5 0

3 years ago

The value of polynomial 5x-4x^2+3, when x=-1​

The value of polynomial 5x-4x^2+3, when x=-1