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Paraphin [41]
3 years ago
11

HELP PLEASE! Solve the system by substitution, please include work

Mathematics
1 answer:
Digiron [165]3 years ago
8 0
For this question you are going to want to isolate a different variable in one of the first two and the third. Then you will plug those values into each other and then the reuslts into the third (I will show later). I will be using the 1st and the 3rd because those are the easiest.
-x-y-z = -8------> add y and z to both sides
-x = y + z - 8 -----> Divide both sides by -1
x = -y - z + 8

2x + 2z = 4 ----> Divide both sides by 2
x + z = 2 -----> Subtract x from both sides
z = -x + 2

x = -y - (-x + 2) + 8 ----> Now reisolate x by first simplying
x = -y + x -2 + 8 -----> Add
x = -y + x + 6 -----> Subtract x from both sides and add y to both sides
y = 6

Plug the values for y and z into the second equation and isolate x.
-4x + 4(6) + 5(-x+2) = 7 ----> Simplify
-4x + 24 -5x +10 = 7 ----> Combine like terms
-9x + 34 = 7 -----> Subtract 34 from both sides
-9x = -27 -----> Divide both sides by -9
x = 3

Plug x into the thirs equation and isolate z
2(3) + 2z = 4 ---> Simplify
6 + 2z = 4 ----> Subtract 6 from both sides
2z = -2 ----> Divide both sizes by 2
z = -1

Final Answers:
x = 3
y = 6
z = -1

Optional - Check your answer by plugging the values above back into the 1st equation.

-x-y-z = -8
-(3)-(6)-(-1) = -8
-3 - 6 + 1 = -8
-8 = -8

Hope this helps!






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Answer:

DF = 458

Step-by-step explanation:

In statistics, T-test have an extensive application. T-tests are used in hypothesis testing or inference about the population mean when the population standard deviation is not known. Nevertheless, they are used in making inference in paired samples or dependent samples t-test as well as independent samples.

The degrees of freedom, DF, is a characteristic of the student's t distribution which is used in T-tests. In a simple T-test;

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Given n is 459, DF = 459 - 1 = 458

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Pani-rosa [81]

Answer:

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Step-by-step explanation:

Ah, the sine law questions. Ok so you know \frac{sin(A)}{a} = \frac{sin(B)}{b} = \frac{sin(C)}{c}. If you don't, voila. Obviously, the variables are different but we can use the same formula. So, we have

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MakcuM [25]

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Step-by-step explanation:

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3 years ago
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aleksandrvk [35]

Answer:

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