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2 years ago

Please help me Im lost on this :(

Mathematics

2 answers:

kkurt [141]2 years ago

7 0

Answer:

Step-by-step explanation:

the quadratic formula is

$\frac{ - b + \sqrt{b ^{2} - 4ac} }{2a}$

Make the quadratic equal to 0, so it will be 3x^2 + 8x -2=0. Then substitute the values into the equation.

xeze [42]2 years ago

6 0

Answer: C) 3x^2+8x-10=-8

Step-by-step explanation:

3x^2+8x-10x=-8

3x^2+8x-2=0

a=3 b=8 c=-2

Plug it into quadratic formula.

You might be interested in

X^2-5x+2 x 3x^2 +2x +3

Katen [24]

Answer:

3x^4 - 13x^3 - x^2 - 11x + 6.

Step-by-step explanation:

x^2-5x+2 x 3x^2 +2x +3

= x^2(3x^2 +2x +3) - 5x(3x^2 +2x +3) + 2(3x^2 +2x +3)

= 3x^4 + 2x^3 + 3x^2 - 15x^3 - 10x^2 - 15x + 6x^2 + 4x + 6

Adding like terms:

= 3x^4 - 13x^3 - x^2 - 11x + 6.

5 0

3 years ago

joe weighs 20lbs.less yhantwice jeffs weight.if jeff would gain 10lbs.,then together they wouldweigh 250lbs. how much does each

masya89 [10]

So,

Let x represent Joe's weight and y represent Jeff's weight.

"Joe weighs 20 lbs. less than twice Jeff's weight."
x = 2y - 20

"If Jeff would gain 10 lbs., then together they would weigh 250 lbs."
(y + 10) + x = 250

We now have our two open sentences.
x = 2y - 20
(y + 10) + x = 250

Get rid of parentheses.
x = 2y - 20
x + y + 10 = 250

We will use Elimination by Substitution.
2y - 20 + y + 10 = 250

Collect Like Terms.
3y - 10 = 250

Add 10 to both sides.
3y = 260

Divide both sides by 3.
$Jeff's\ weight = 86 \frac{2}{3} \ lbs.$

Substitute again.
$x = 2(86 \frac{2}{3} )-20$

Multiply.
$x = 173 \frac{1}{3} -20$

Subtract.
$Joe's\ weight = 153 \frac{1}{3}\ lbs.$

Check.

"Joe weighs 20 lbs. less than twice Jeff's weight."
Jeff's weight times two is 173 and one-third.
20 lbs. less than that is 153 and one-third lbs. Check.

"If Jeff would gain 10 lbs., then together they would weigh 250 lbs."
86 and two-thirds + 10 = 96 and two-thirds.
96 and two-thirds + 153 and one-third equals 250 lbs. Check.

$Joe's\ weight\ is\ 153 \frac{1}{3} \ lbs.$
$Jeff's\ weight\ is\ 86 \frac{2}{3} \ lbs.$

3 0

3 years ago

Which lists the steps in the correct order to find the median of this data set?

Fofino [41]

The median of the data set can be found as follows:

1. Put the numbers in order (from least to the greatest): 16, 18, 23, 24, 29, 30

2. Cross off high/low pairs: 16, 18, (23, 24,) 29, 30

3. Divide the sum by 2: (23 + 24)/2 = 23.5

<h3>What is the Median?</h3>

The median of a data set is the data value at the middle of the data set when it is ordered.

Steps to find the median of the data set, 24, 16, 23, 30, 18, 29:

1. Put the numbers in order (from least to the greatest)

16, 18, 23, 24, 29, 30

2. Cross off high/low pairs: 16, 18, (23, 24,) 29, 30

3. Divide the sum by 2: (23 + 24)/2 = 23.5

The median is therefore, 23.5.

Learn more about the median on:

brainly.com/question/26177250

3 0

2 years ago

It is known that the population variance equals 484. With a .95 probability, the sample size that needs to be taken to estimate

Hitman42 [59]

Answer:

The minimum sample size is n = 75 so that the desired margin of error is 5 or less.

Step-by-step explanation:

We are given the following in the question:

Population variance = 484

Standard deviation =

$\sigma^2 = 484\\\sigma =\sqrt{484} = 22$

Confidence level = 0.95

Significance level = 0.05

Margin of error = 5

Formula:

Margin of error =

$E = z\times \dfrac{\sigma}{\sqrt{n}}\\\\n = (\dfrac{z\times \sigma}{E})^2$

$z_{critical}\text{ at}~\alpha_{0.05} = 1.96$

Putting values, we get

$E\leq 5\\\\1.96\times \dfrac{22}{\sqrt{n}} \leq 5\\\\\sqrt{n} \geq 1.96\times \dfrac{22}{5}\\\\n \geq (1.96\times \dfrac{22}{5})^2\\\\n \geq 74.373$

Thus, the minimum sample size is n = 75 so that the desired margin of error is 5 or less.

3 0

3 years ago

Question 1 (Multiple Choice Worth 4 points)

VLD [36.1K]

Answer:

In the first expression:

(5^3)^-4 = 5^-12

Step-by-step explanation:

4 0

3 years ago

Please help me Im lost on this :(​

Please help me Im lost on this :(