Since the equation was solved for `z` , replace all occurrences of `z` in the other equations with the solution `(-3x+2y+1)` .
`z=-3x+2y+1 `
`x+y+(-3x+2y+1)=4 `
`2x+2y-3(-3x+2y+1)=8 `
Remove the parentheses around the expression `-3x+2y+1` .
`z=-3x+2y+1 `
`x+y-3x+2y+1=4 `
`2x+2y-3(-3x+2y+1)=8`
Combine all similar terms in the polynomial `x+y-3x+2y+1` .
`z=-3x+2y+1`
`-2x+3y+1=4`
`2x+2y-3(-3x+2y+1)=8`
Multiply `-3` by each term inside the parentheses.
`z=-3x+2y+1`
`-2x+3y+1=4`
`2x+2y+9x-6y-3=8`
Combine all similar terms in the polynomial `2x+2y+9x-6y-3` .
`z=-3x+2y+1 `
`-2x+3y+1=4`
`11x-4y-3=8`
Move all terms not containing `x` to the right-hand side of the equation.
`z=-3x+2y+1`
`-2x=3-3y`
`11x-4y-3=8`
Divide each term in the equation by `-2` .
`z=-3x+2y+1`
`x = (3y)/2 - 3/2`
`11x-4y-3=8 `
Since the equation was solved for `x` , replace all occurrences of `x` in the other equations with the solution `((3y)/2 - 3/2).`
`z=-3x+2y+1 `
`x = (3y)/2 - 3/2`
`11 ((3y)/2 - 3/2) - 4y - 3= 8`
Multiply `11` by each term inside the parentheses.
`z=-3x+2y+1`
`x = (3y)/2 - 3/2`
`(33y)/2 - (33)/2 - 4y - 3 = 8`
Combine `(33y)/2 - 4y` into a single expression by finding the least common denominator (LCD). The LCD of `(33y)/2 - 4y` is `2` .
`z=-3x+2y+1 `
`x = (3y)/2 - 3/2`
`(25y)/2 - (33)/2 - 3 = 8`
Combine `-(33)/2 - 3` into a single expression by finding the least common denominator (LCD). The LCD of `-(33)/2 - 3` is `2` .
`z=-3x+2y+1 `
`x = (3y)/2 - 3/2`
`(25y)/2 - (39)/2 = 8`
Move all terms not containing `y` to the right-hand side of the equation.
`z=-3x+2y+1`
`x = (3y)/2 - 3/2`
`(25y)/2 = (55)/2`
Multiply `55 * 2` to get `110` in the numerator.
`z=-3x+2y+1`
`x = (3y)/2 - 3/2`
`25 y = (110)/2`
Reduce the expression by canceling out all common factors from the numerator and denominator.
`z=-3x+2y+1`
`x = (3y)/2 - 3/2`
`25y=55`
Since the equation was solved for `y` , replace all occurrences of `y` in the other equations with the solution `(11/5).`
`z=-3x+2y+1`
`x = (3y)/2 - 3/2`
`y = 11/5`
Since the equation was solved for `y` , replace all occurrences of `y` in the other equations with the solution `(11/5)`
`z = -3x + 2 (11/5) + 1`
`x = (3(11/5))/2 - 3/2`
`y = 11/5`
Multiply `2` by each term inside the parentheses.
`z = -3x + 22/5 + 1`
`x = (3(11/5))/2 - 3/2`
`y = 11/5`
Combine `22/5 + 1` into a single expression by finding the least common denominator (LCD). The LCD of `22/5 + 1` is `5` .
`z = -3x + 27/5`
`x = (3(11/5))/2 - 3/2`
`y = 11/5`
Remove the single term factors from the expression.
`z = 27/5 - 3x`
`x = 33/10 - 3/2`
`y = 11/5`
Remove the parentheses from the numerator.
`z = 27/5 - 3x`
`x = 18/10`
`y = 11/5`
Combine `33/10 - 3/2` into a single expression by finding the least common denominator (LCD). The LCD of `33/10 - 3/2` is `10` .
`z = 27/5 - 3x`
`x = 9 /5`
`y = 11/5`
Since the equation was solved for `x` , replace all occurrences of `x` in the other equations with the solution `(9/5)`
`z = 27/5 - 3(9/5)`
`x = 9/5`
`y = 11/5`
Multiply `-3` by each term inside the parentheses.
`z = 27/5 - 27/5`
`x = 9/5`
`y = 11/5`
Combine all similar expressions.
`z=0 `
`x = 9/5`
`y = 11/5`
This is the solution to the system of equations.
`z=0`
`x = 9/5`
`y = 11/5`
The system of equations:
3x - 2y + z = 1 ...(1)
x + y + z = 4 ...(2)
2x + 2y - 3z = 8 ...(3)
has to be solved for x, y and z.
(3) - 2*(2)
=> 2x + 2y - 3z - 2*(x + y + z) = 8 - 8
=> 2x + 2y - 3z - 2x - 2y - 2z = 0
=> -5z = 0
=> z = 0
Substituting z = 0 in (1) and (3) gives 3x - 2y = 1 and 2x + 2y = 8
Adding the two equations gives `5x = 9 => x = 9/5`
Substituting x = 9/5 in 3x - 2y = 1 gives 3*(9/5) - 2y = 1
=> 2y = 27/5 - 1
=> 2y = 22/5
=> y = 11/5
The solution of the given set of equations is x = 9/5, y = 11/5 and z = 0
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