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3 years ago

Solve the linear equation 31x + 29y = 33 29x + 31y = 27

Mathematics

1 answer:

Temka [501]3 years ago

6 0

Answer:

x = 2

y = -1

Step-by-step explanation:

Make the coefficient of x the same

Multiply the first equation by 29

31x + 29y = 33 becomes

899x + 841y = 957

Multiply the second equation by 31

29x + 31y = 27 becomes

899x + 961y = 837

Subtract the equations

(899x + 841y) - (899x + 961y) = 957 - 837

(899x - 899x) + (841y - 961y) = 120

841y - 961y = 120

-120y = 120

y = 120/-120 = -1

Substitute the value of y into both equations to find the value of x and check its right.

31x + 29y = 33

31x + 29(-1) = 33

31x - 29 = 33

31x = 33 + 29

31x = 62

x = 62/31 = 2

29x + 31y = 27

29x + 31(-1) = 27

29x - 31 = 27

29x = 27 + 31

29x = 58

x = 58/29 = 2

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Factor a trinomial.
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Set the factor '(-5 + -1x)' equal to zero and attempt to solve:

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Subproblem 2:

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3 years ago

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Pie

Answer:

Yes it involves a statistical test

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The null hypothesis is $H_o : \mu_R = \mu_L$ ,

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