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Solve the following equations:
6x - 4y+3z= −10
3x−5y - 3z= −1
−5x + 6y−3z= 5

1 Answer

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Final answer:

To solve the system of equations, we will use the method of elimination to eliminate variables one at a time. This will result in a system of two equations with two variables, which can be solved by substitution or elimination. The solution to the system is x = -4.38, y = 1.34, and z = 7.21.

Step-by-step explanation:

To solve the simultaneous equations:

Equation 1: 6x - 4y + 3z = -10

Equation 2: 3x - 5y - 3z = -1

Equation 3: -5x + 6y - 3z = 5

Step 1: We can use the method of elimination to eliminate one variable at a time. Start by cancelling out the y variable. Multiply Equation 1 by 3 and Equation 2 by 6:

18x - 12y + 9z = -30

18x - 30y - 18z = -6

Step 2: Subtract Equation 2 from Equation 1:

18x - 12y + 9z - 18x + 30y + 18z = -30 - (-6)

42y + 27z = -24

Step 3: Multiply Equation 1 by 5 and Equation 3 by 6:

30x - 20y + 15z = -50

-30x + 36y - 18z = 30

Step 4: Add Equation 3 to Equation 1:

30x - 20y + 15z - 30x + 36y - 18z = -50 + 30

16y - 3z = -20

Step 5: Now we have a system of two equations with two variables:

42y + 27z = -24

16y - 3z = -20

Step 6: Solve the system using any method you prefer. For simplicity, let's use the method of elimination again. Multiply the second equation by 7:

112y - 21z = -140

42y + 27z = -24

Step 7: Subtract the second equation from the first:

112y - 21z - 42y - 27z = -140 - (-24)

70y - 48z = -116

Step 8: Now we have a system of two linear equations with two variables:

70y - 48z = -116

16y - 3z = -20

Step 9: Solve the system using any method you prefer. For simplicity, let's use the method of substitution. Solve Equation 2 for y:

y = (3z - 20)/16

Step 10: Substitute this value of y into Equation 1:

70(3z - 20)/16 - 48z = -116

210z - 1400 - 48z = -232C

162z - 1400 = -232

162z = -232 + 1400

162z =1168

z = 1168/162

z = 7.21

Step 11: Substitute the value of z into the equation for y:

y = (3(7.21) - 20)/16

y = 21.47/16

y = 1.34

Step 12: Substitute the values of y and z into any of the original equations to solve for x. Let's use Equation 1:

6x - 4(1.34) + 3(7.21) = -10

6x - 5.36 + 21.63 = -10

6x + 16.27 = -10

6x = -10 - 16.27

6x = -26.27

x = -26.27/6

x = -4.38

Step 13: Therefore, the solution to the system of equations is

x = -4.38,

y = 1.34, and

z = 7.21.

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