Please solve this it's on khan academy :( oo

Novay_Z [31]

Y=((square root of 2)+1)
$c = 2.2403703492$
$e = 5.71307488659$

1) (y-1)^2 =2
so we can concludes that y-1 = squareroot of 2
so ((squareeroot of 2+1) - 1)^2 = 2

2)First we can convert 21÷2 fraction to decmial form which is 10.5
so our equation would be (c+1)^2= 10.5
so c+1 is the sqaureroot root of 10.5
so c would be the (square root of 10.5)-1

3)We can again convert those fractions to decimals so 3/2=1.5 and 71/4 =17.75
so our equation would be (e-1.5)^2=17.75
so (e-1.5) is the square root of 17.75
so e=((square root of 17.75)+1)

8 0

3 years ago

Round 11,900 to the nearest thousand.<br><br> 5 stars for a correct answer.

Oksi-84 [34.3K]

Answer:

12,000

Step-by-step explanation:

The two thousands that 11,900 is in between are 11,000 and 12,000 which are our two options to choose from. 11,900 is only 100 away from 12,000 and 900 away from 11,000. Because the distance between 11,900 and 12,000 is shorter than the distance between 11,900 and 11,000, this means that 12,000 would be our answer since it is closer.

(I'm really sorry if this is confusing, I'm not good with words)

7 0

3 years ago

Read 2 more answers

1) Lithium isotope rations are important to medicine, the 6Li/7Li ratio in a standard reference material was measured several ti

uysha [10]

Answer:

1) $0.0826052-2.776\frac{0.000013424}{\sqrt{5}}=0.082588$

$0.0826052+2.776\frac{0.000013424}{\sqrt{5}}=0.0826219$

b) $ME= 2.776\frac{0.000013424}{\sqrt{5}}=0.0000166653$

And we want 2/3 of the margin of error so then would be: $2/3 ME = 0.00001111$

The margin of error is given by this formula:

$ME=z_{\alpha/2}\frac{s}{\sqrt{n}}$ (1)

And on this case we have that ME =0.00001111016 and we are interested in order to find the value of n, if we solve n from equation (1) we got:

$n=(\frac{z_{\alpha/2} s}{ME})^2$ (2)

Replacing we got:

$n=(\frac{2.776(0.000013424)}{0.00001111})^2 =11.25 \approx 12$

So the answer for this case would be n=12 rounded up to the nearest integer

Step-by-step explanation:

Information given

0.082601, 0.082621, 0.082589, 0.082617, 0.082598

We can calculate the sample mean and deviation with the following formulas:

$\bar X= \frac{\sum_{i=1}^n X_i}{n}$

$s = \sqrt{\frac{\sum_{i=1}^n (X_i -\bar X)^2}{n-1}}$

$\bar X=0.0826052$ represent the sample mean

$\mu$ population mean

s=0.000013424 represent the sample standard deviation

n=5 represent the sample size

Part 1

The confidence interval for the mean is given by the following formula:

$\bar X \pm t_{\alpha/2}\frac{s}{\sqrt{n}}$ (1)

The degrees of freedom, given by:

$df=n-1=5-1=4$

The Confidence level is 0.95 or 95%, and the significance would be $\alpha=0.05$ and $\alpha/2 =0.025$ , the critical value would be using the t distribution with 4 degrees of freedom: $t_{\alpha/2}=2.776$

Now we have everything in order to replace into formula (1):

$0.0826052-2.776\frac{0.000013424}{\sqrt{5}}=0.082588$

$0.0826052+2.776\frac{0.000013424}{\sqrt{5}}=0.0826219$

Part 2

The original margin of error is given by:

$ME= 2.776\frac{0.000013424}{\sqrt{5}}=0.0000166653$

And we want 2/3 of the margin of error so then would be: $2/3 ME = 0.00001111$

The margin of error is given by this formula:

$ME=z_{\alpha/2}\frac{s}{\sqrt{n}}$ (1)

And on this case we have that ME =0.00001111016 and we are interested in order to find the value of n, if we solve n from equation (1) we got:

$n=(\frac{z_{\alpha/2} s}{ME})^2$ (2)

Replacing we got:

$n=(\frac{2.776(0.000013424)}{0.00001111})^2 =11.25 \approx 12$

So the answer for this case would be n=12 rounded up to the nearest integer

3 0

3 years ago

I need help finding the side AB NOT THE ANGE AB which is 90°

Sindrei [870]

Answer:

AB = 10.83 cm

Step-by-step explanation:

From ΔABC,

m∠B = 90°

By applying sine rule in the given triangle,

sinθ = $\frac{\text{Opposite side}}{\text{Hypotenuse}}$

sin(37°) = $\frac{AB}{AC}$

AB = AC(sin37°)

AB = 18×(0.060182)

= 10.833

≈ 10.83 cm

Therefore, AB = 10.83 cm is the answer.

8 0

3 years ago

Answer this question please and thank you

ELEN [110]

Answer:

x = -11

-11-3=-14

-14/7=-2

7 0

3 years ago