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1 year ago

Pleaseee help, question what is the sum of 4x^2 + 2x - 5 and 7x^2 - 5x + 2

Mathematics

2 answers:

Nataliya [291]1 year ago

6 0

Simplification of polynomials.

Polynomials <em>are</em> mathematical expressions made up of many terms.<em>To</em> simplify a polynomial <em>the most, you must collect all</em><em> </em>like terms <em>and rearrange them from highest to lowest power.</em>

<h3>4x² + 2x -5 + 7x² - 5x+2</h3><h3>4x² + 2x -3 + 7x² - 5x+2</h3><h3>11x² + 2x - 3 - 5x</h3><h3>11x² - 3x - 3 ====> Option "A"</h3>

AlladinOne [14]1 year ago

3 0

Answer:

Add the expressions.

11x2−3x−3

Step-by-step explanation:

You might be interested in

Look at photo for question. Do number 3 A-D?

Digiron [165]

Answer:

A: 6, 12, 18, 24, 30

10, 20, 30, 40

B: 30

C: 5/6= 25/30 and 7/10= 21/30

D: 25/30>21/30 so 5/6>7/10

8 0

2 years ago

According to a Yale program on climate change communication survey, 71% of Americans think global warming is happening.† (a) For

SpyIntel [72]

Answer:

a) 0.2741 = 27.41% probability that at least 13 believe global warming is occurring

b) 0.7611 = 76.11% probability that at least 110 believe global warming is occurring

Step-by-step explanation:

Binomial probability distribution

The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

In which $C_{n,x}$ is the number of different combinations of x objects from a set of n elements, given by the following formula.

$C_{n,x} = \frac{n!}{x!(n-x)!}$

And p is the probability of X happening.

The expected value of the binomial distribution is:

$E(X) = np$

The standard deviation of the binomial distribution is:

$\sqrt{V(X)} = \sqrt{np(1-p)}$

Normal probability distribution

Problems of normally distributed samples can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

When we are approximating a binomial distribution to a normal one, we have that $\mu = E(X)$ , $\sigma = \sqrt{V(X)}$ .

In this problem, we have that:

$p = 0.71$

(a) For a sample of 16 Americans, what is the probability that at least 13 believe global warming is occurring?

Here $n = 16$ , we want $P(X \geq 13)$ . So

$P(X \geq 13) = P(X = 13) + P(X = 14) + P(X = 15) + P(X = 16)$

In which

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

$P(X = 13) = C_{16,13}.(0.71)^{13}.(0.29)^{3} = 0.1591$

$P(X = 14) = C_{16,14}.(0.71)^{14}.(0.29)^{2} = 0.0835$

$P(X = 15) = C_{16,15}.(0.71)^{15}.(0.29)^{1} = 0.0273$

$P(X = 16) = C_{16,16}.(0.71)^{16}.(0.29)^{0} = 0.0042$

$P(X \geq 13) = P(X = 13) + P(X = 14) + P(X = 15) + P(X = 16) = 0.1591 + 0.0835 + 0.0273 + 0.0042 = 0.2741$

0.2741 = 27.41% probability that at least 13 believe global warming is occurring

(b) For a sample of 160 Americans, what is the probability that at least 110 believe global warming is occurring?

Now $n = 160$ . So

$\mu = E(X) = np = 160*0.71 = 113.6$

$\sigma = \sqrt{V(X)} = \sqrt{np(1-p)} = \sqrt{160*0.71*0.29} = 5.74$

Using continuity correction, this is $P(X \geq 110 - 0.5) = P(X \geq 109.5)$ , which is 1 subtracted by the pvalue of Z when X = 109.5. So

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{109.5 - 113.6}{5.74}$

$Z = -0.71$

$Z = -0.71$ has a pvalue of 0.2389

1 - 0.2389 = 0.7611

0.7611 = 76.11% probability that at least 110 believe global warming is occurring

3 0

3 years ago

If RS= 3x + 1 , ST= 2x -2 , RT= 64 , fine the value of x

Novay_Z [31]

The answer is

RS=3 x 2 + 1, ST= 2 x 4 -2, RT= 64, i'm sorry if it didn't help

6 0

3 years ago

Let the sample space be Upper S equals StartSet 1 comma 2 comma 3 comma 4 comma 5 comma 6 comma 7 comma 8 comma 9 comma 10 EndSe

Marina86 [1]

Answer:

Probability of event E = (4/10) = 0.40

Step-by-step explanation:

Note that n(E) is the number of outcomes in E

n(S) is the number of outcomes in S

And with each outcome having equal likelihood of occurring,

SetS = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10}.

n(S) = 10

Event E = {1, 4, 7, 9}.

n(E) = 4

Probability of event E = n(E)/n(S)

Probability of event E = (4/10) = 0.40

Hope this Helps!!

4 0

3 years ago

Find the solutions to 2x^5-5x^3-3x=0. What are the x-intercepts of the graph of the function f(x)=2x^5-5x^3-3x?

Olegator [25]

Answer:

Solution

roots: ( $(-\sqrt{3} ) (0,0) (\sqrt{3}$ )

domain X∈3

vertical intercept (0,0)

x = {0, -1.732050808, 1.732050808}

Please, find attached images equation graphs

Step-by-step explanation:

Simplifying

2x5 + -5x3 + -3x = 0

Reorder the terms:

-3x + -5x3 + 2x5 = 0

Solving

-3x + -5x3 + 2x5 = 0

Solving for variable 'x'.

Factor out the Greatest Common Factor (GCF), 'x'.

x(-3 + -5x2 + 2x4) = 0

Factor a trinomial.

x((-1 + -2x2)(3 + -1x2)) = 0

Subproblem 1

Set the factor 'x' equal to zero and attempt to solve:

Simplifying

x = 0

Solving

x = 0

Move all terms containing x to the left, all other terms to the right.

Simplifying

x = 0

Subproblem 2

Set the factor '(-1 + -2x2)' equal to zero and attempt to solve:

Simplifying

-1 + -2x2 = 0

Solving

-1 + -2x2 = 0

Move all terms containing x to the left, all other terms to the right.

Add '1' to each side of the equation.

-1 + 1 + -2x2 = 0 + 1

Combine like terms: -1 + 1 = 0

0 + -2x2 = 0 + 1

-2x2 = 0 + 1

Combine like terms: 0 + 1 = 1

-2x2 = 1

Divide each side by '-2'.

x2 = -0.5

Simplifying

x2 = -0.5

The solution to this equation could not be determined.

This subproblem is being ignored because a solution could not be determined.

Subproblem 3

Set the factor '(3 + -1x2)' equal to zero and attempt to solve:

Simplifying

3 + -1x2 = 0

Solving

3 + -1x2 = 0

Move all terms containing x to the left, all other terms to the right.

Add '-3' to each side of the equation.

3 + -3 + -1x2 = 0 + -3

Combine like terms: 3 + -3 = 0

0 + -1x2 = 0 + -3

-1x2 = 0 + -3

Combine like terms: 0 + -3 = -3

-1x2 = -3

Divide each side by '-1'.

x2 = 3

Simplifying

x2 = 3

Take the square root of each side:

x = {-1.732050808, 1.732050808}

Solution

x = {0, -1.732050808, 1.732050808}

3 0

3 years ago