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x+2y+z=7 x+3z=11 2x-3y=1...

x+2y+z=7
x+3z=11
2x-3y=1

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To solve the system of linear equations given by: 1. \( x + 2y + z = 7 \) (Equation 1) 2. \( x + 3z = 11 \) (Equation 2) 3. \( 2x - 3y = 1 \) (Equation 3) we will follow these steps: ### Step 1: Multiply Equation 1 by 3 We will multiply the first equation by 3 to eliminate \( z \) later when we combine it with Equation 2. \[ 3(x + 2y + z) = 3(7) \] This gives us: \[ 3x + 6y + 3z = 21 \quad \text{(Equation 4)} \] ### Step 2: Write Equation 2 We will keep Equation 2 as it is for now: \[ x + 3z = 11 \quad \text{(Equation 2)} \] ### Step 3: Subtract Equation 2 from Equation 4 Now we will subtract Equation 2 from Equation 4 to eliminate \( z \). \[ (3x + 6y + 3z) - (x + 3z) = 21 - 11 \] This simplifies to: \[ 3x - x + 6y + 3z - 3z = 10 \] \[ 2x + 6y = 10 \quad \text{(Equation 5)} \] ### Step 4: Simplify Equation 5 We can simplify Equation 5 by dividing everything by 2: \[ x + 3y = 5 \quad \text{(Equation 6)} \] ### Step 5: Use Equation 3 Now we will use Equation 3: \[ 2x - 3y = 1 \quad \text{(Equation 3)} \] ### Step 6: Solve Equations 6 and 3 Now we have a new system of equations: 1. \( x + 3y = 5 \) (Equation 6) 2. \( 2x - 3y = 1 \) (Equation 3) We can add these two equations to eliminate \( y \): \[ (x + 3y) + (2x - 3y) = 5 + 1 \] This simplifies to: \[ 3x = 6 \] Thus, we find: \[ x = 2 \] ### Step 7: Substitute \( x \) back into Equation 6 Now we will substitute \( x = 2 \) back into Equation 6 to find \( y \): \[ 2 + 3y = 5 \] Subtracting 2 from both sides gives: \[ 3y = 3 \] Thus, we find: \[ y = 1 \] ### Step 8: Substitute \( x \) into Equation 2 to find \( z \) Now we will substitute \( x = 2 \) into Equation 2 to find \( z \): \[ 2 + 3z = 11 \] Subtracting 2 from both sides gives: \[ 3z = 9 \] Thus, we find: \[ z = 3 \] ### Final Solution The values of \( x \), \( y \), and \( z \) are: \[ x = 2, \quad y = 1, \quad z = 3 \]
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