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3 years ago

Plz help me with 6th grade math- I’m dumb

Mathematics

1 answer:

svlad2 [7]3 years ago

4 0

It’s length times width time height so the first one should be 75 and I have a link to answer them reply If you want it?

You might be interested in

What are the solutions of the equation 9x4 – 2x2 – 7 = 0? Use u substitution to solve. tions of the equation 9

skelet666 [1.2K]

Answer:

Step-by-step explanation:

Let $u^2=x^4\\u = x^2$

Subbing in:

$9u^2-2u-7=0$

a = 9, b = -2, c = -7

The product of a and c is the aboslute value of -63, so a*c = 63. We need 2 factors of 63 that will add to give us -2. The factors of 63 are {1, 63}, (3, 21}, {7, 9}. It looks like the combination of -9 and +7 will work because -9 + 7 = -2. Plug in accordingly:

$9u^2-9u+7u-7=0$

Group together in groups of 2:

$(9u^2-9u)+(7u-7)=0$

Now factor out what's common within each set of parenthesis:

$9u(u-1)+7(u-1)=0$

We know this combination "works" because the terms inside the parenthesis are identical. We can now factor those out and what's left goes together in another set of parenthesis:

$(u-1)(9u+7)=0$

Remember that $u=x^2$

so we sub back in and continue to factor. This was originally a fourth degree polynomial; that means we have 4 solutions.

$(x^2-1)(9x^2+7)=0$

The first two solutions are found withing the first set of parenthesis and the second two are found in other set of parenthesis. Factoring $(x^2-1)$ gives us that x = 1 and -1. The other set is a bit more tricky. If

$9x^2+7=0$ then

$9x^2=-7$ and

$x^2=-\frac{7}{9}$

You cannot take the square root of a negative number without allowing for the imaginary component, i, so we do that:

$x=$ ± $\sqrt{-\frac{7}{9} }$

which will simplify down to

$x=$ ± $\frac{\sqrt{7} }{3}i$

Those are the 4 solutions to the quartic equation.

5 0

4 years ago

Le Saveu The UL health centre is giving a Pfizer vaccine to the surrounding community members of the 100 people who were vaccina

enot [183]

Using confidence interval concepts, it is found that the incorrect statement is given by:

B. The population proportion is 0.80.

In a sample of n people with a proportion of $\pi$ , and a confidence level of $1-\alpha$ , we the confidence interval for the proportion is:

$\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}$

In which z is the z-score that has a p-value of $1 - \frac{\alpha}{2}$ .

80 developed immunity out of 100, thus, the sample proportion is:

$\pi = \frac{80}{100} = 0.8$

Option A is correct.

The standard error is:

$s = \sqrt{\frac{\pi(1-\pi)}{n}}$

Considering $n = 100$

$s = \sqrt{\frac{0.8(0.2)}{100}} = 0.04$

Thus, statement E is correct.

90% confidence level, thus the critical value is the value of z that has a p-value of $1 - \frac{0.05}{2} = 0.975$ , so $z = 1.645$ , which means that statement D is correct.

The margin of error is:

$M = zs = 1.645(0.04) = 0.0658$

Thus, statement C is correct, which leaves B as the false statement, as we have the sample proportion, and we can only estimate, not guarantee the population proportion.

A similar problem is gien at brainly.com/question/16807970

5 0

3 years ago

Can you simplify 54/72 if so by what number?

iogann1982 [59]

54/72 gets reduced to 27/36 by the number 2 :)

6 0

4 years ago

with a mean of 32 minutes and a standard deviation of 5 minutes. What is the probability that a randomly selected customer will

Gala2k [10]

Answer:

1.39%

Step-by-step explanation:

(21 - 32) / 5 = -2.2 z score

= 0.0139 so there is a 1.39% probability

4 0

3 years ago

DO NOT SKIP LETS SO WHOS SMART ENOUGH TO ANSWER THESE 2 PROBLEMS I CHALLENGE YOU!!

rodikova [14]

Q 16. The energy is 308.7 J.

Q 17. The energy is 896000 J.

Step-by-step explanation:

Q 16. Given,

Mass (m) of the carriage and baby = 1.5 kg

Height (h) = 21 m

To find the energy.

We will find the potential energy as it rests at the top.

Formula

Potential energy = mgh where g be the gravitational force of the earth = 9.8m/s²

So,

Energy = 1.5×9.8×21 J

= 308.7 J.

Hence,

The energy is 308.7 J.

Q 17. Given,

Mass (m) = 1120 kg

Speed (v) = 40 m/s

To find out the energy.

We will find out the kinetic energy as the car is in motion.

Formula

Kinetic energy = $\frac{1}{2}$ mv²

So,

Energy = $\frac{1}{2}$ ×1120×40² J

= 896000 J

Hence,

The energy is 896000 J.

7 0

4 years ago