-3x+7 x=-2 PLEASE SHOW WORK. Thanks

Mathematics

1 answer:

galben [10]3 years ago

5 0

Answer:

1 :

Step 2 :

Equations which are never true :

2.1 Solve : 2 = 0

This equation has no solution.

A a non-zero constant never equals zero.

Solving a Single Variable Equation :

2.2 Solve : 2x+1 = 0

Subtract 1 from both sides of the equation :

2x = -1

Divide both sides of the equation by 2:

x = -1/2 = -0.500

One solution was found :

x = -1/2 = -0.500

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sashaice [31]

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3 years ago

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Effectus [21]

Answer:

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Step-by-step explanation:

Let X1` be the mean of the first random sample of size n1 from a normal population with a mean u1 and known standard deviation σ1.Let X2` be the mean of the second random sample of size n2 from another normal population with a mean u2 and known standard deviation σ2. Then the sampling distribution of the difference X1`-X2` is normally distributed with a mean of u1-u2 and a standard deviation of

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Z= (X1`-X2`)- (u1-u2)/ $\sqrt{ \frac{ s_1^2}{n_1^2} +\frac{ s_2^2}{n_2}$ (here s1=σ1 and s2= σ2)

is exactly standard normal no matter how small sample sizes are . Hence it is used as a test statistic for testing hypotheses about the difference between two population means.

The procedure is stated below.

1) Formulate the null and alternative hypotheses.

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6) Rehect H0 if Z falls in the critical region, accept H0 , otherwise.

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son4ous [18]

Answer: