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3 years ago

Evaluate b2c-1 for b = 8 and c = -4. -16 1/16 16 256

Mathematics

2 answers:

Bumek [7]3 years ago

7 0

B²c-¹ = (8)²(–4)-¹ = 64(–¼) = –16

nata0808 [166]3 years ago

7 0

Answer: The correct option is (B) -16.

Step-by-step explanation: We are given to evaluate the value of the following expression for b = 8 and c = -4 :

$E=b^2c^{-1}.$

To find the value of expression (i), we need to substitute the values of b and c in equation (i).

We will be using the following property of exponents :

$x^{-a}=\dfrac{1}{x^a}.$

Therefore, from equation (i), we get

$E\\\\=b^2c^{-1}\\\\=8^2\times (-4)^{-1}\\\\\\=\dfrac{64}{-4}\\\\=-16.$

Thus, option (B) is correct.

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An engineer designed a valve that will regulate water pressure on an automobile engine. The engineer designed the valve such tha

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We conclude that the valve performs above the specifications.

Step-by-step explanation:

We are given the following in the question:

Population mean, μ = 6.3 pounds per square inch

Sample mean, $\bar{x}$ = 6.5 pounds per square inch

Sample size, n = 130

Alpha, α = 0.02

Population standard deviation, σ = 0.8

First, we design the null and the alternate hypothesis

$H_{0}: \mu = 6.3\text{ pounds per square inch}\\H_A: \mu > 6.3\text{ pounds per square inch}$

We use one-tailed z test to perform this hypothesis.

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Decision rule:

If the calculated statistic is greater than the the critical value, we reject the null hypothesis and if the calculated statistic is lower than the the critical value, we accept the null hypothesis

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3 years ago

A zipline is constructed over a ravine as shown in the diagram at the right. What is the horizontal distance from the bottom of

Katyanochek1 [597]

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Sin50/250 = SinY/60

Set up your problem, then cross multiply.

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After cross multiplying, you should be left with this. You then cancel out 250 by dividing it on both sides to get Sin Y by itself.

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This is what it solves out to.

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Set up your final problem as so and cross multiply.

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Step-by-step explanation:

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