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3 years ago

4x-5y=13

Mathematics

1 answer:

love history [14]3 years ago

8 0

Hello :
4x-5y=13...(1)
x+5y=-3...(2)
(1)+(2) : 5x = 10
x=2
subsct in (2) : 2+5y = -3
5y =-5
y = -1

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Item a:

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Item b:

Since the test statistic is less than the critical value for the left-tailed test, there is enough evidence to conclude that the null hypothesis will be rejected.

You can learn more about the use of the z-distribution to test an hypothesis at brainly.com/question/16313918

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