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3 years ago

Please answer quickly, I need to get this done. I'll mark brainliest.

Mathematics

1 answer:

worty [1.4K]3 years ago

7 0

J (-4, 1), K (-4, -2), L (-3, -1)

(a) To rotate a point 90° counterclockwise about the origin, multiply the y-coordinate by -1 and then interchange the z- and y- coordinates.

(x, y)'' = (-y, x)

Substitute all of J (-4, 1), K (-4, -2), L (-3, -1) for (x, y)

Solution:

J'' = J (-4, 1) × (x, -1) = (-4, -1)

K'' = K (-4, -2) × (x, -1) = (-4, 2)

L'' = L (-3, -1) × (x, -1) = (-3, 1)

J'' (-1, -4), K'' (2, -4), L'' (1, -3)

Image ▲J"K"L": Look at the first attached picture.

(b) To reflect a point in the y-axis, we multiply its x-coordinate by -1.

Substitute all of J (-4, 1), K (-4, -2), L (-3, -1) for (x, y)

Multiplying by -1:

J'' = J (-4, 1) × (-1, y) = (4, 1)

K'' = K (-4, -2) × (-1, y) = (4, -2)

L'' = L (-3, -1) × (-1, y) = (3, -1)

J'' (4, 1), K'' (4, -2), L'' (3, -1)

Image ▲J"K"L": Look at the second attached picture.

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Part A:

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Part B:

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Part C:

A reduction in the significance level causes a reduction in the power of the test.

Part D:

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Step-by-step explanation:

We have a restaurant with hire a proprotion of 15 % of people in the age ragne of 30-50 years. The expected proportion, according to the applicants, is 50%.

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Part A:

The null and alternative hypothesis are:

$H_0: \pi=0.5\\\\H_1: \pi\neq 0.5$

Part B:

Part C:

The power of an hypothesis test is the probability that the test rejects the null hypothesis (H_0) when a specific alternative hypothesis (H_1) is true.

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Then, a reduction in the significance level causes a reduction in the power of the test.

Part D:

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3 years ago

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Answer:

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please mark brainliest :)

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3 years ago

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