Problem to solve
Solve \[2x-\frac{y}{3}+2z=-1\], \[x+y+\frac{z}{2}=-1\], \[x-2y+z=2\]
Solution
STEP 1
Solve the following system:
{2 x - y/3 + 2 z = -1
x + y + z/2 = -1
x - 2 y + z = 2
STEP 2
Hint: | Choose an equation and a variable to solve for.
In the second equation, look to solve for y:
{2 x - y/3 + 2 z = -1
x + y + z/2 = -1
x - 2 y + z = 2
STEP 3
Hint: | Solve for y.
Subtract z/2 + x from both sides:
{2 x - y/3 + 2 z = -1
y = (-z/2 - x) - 1
x - 2 y + z = 2
STEP 4
Hint: | Perform a substitution.
Substitute y = -z/2 - x - 1 into the first and third equations:
{2 x + 1/3 (z/2 + x + 1) + 2 z = -1
y = -z/2 - x - 1
x - 2 (-z/2 - x - 1) + z = 2
STEP 5
Hint: | Expand the left hand side of the equation 2 x + 1/3 (z/2 + x + 1) + 2 z = -1.
2 x + (z/2 + x + 1)/3 + 2 z = 2 x + (z/6 + x/3 + 1/3) + 2 z = (13 z)/6 + (7 x)/3 + 1/3:
{((13 z)/6 + (7 x)/3 + 1/3) = -1
y = -z/2 - x - 1
x - 2 (-z/2 - x - 1) + z = 2
STEP 6
Hint: | Expand the left hand side of the equation x - 2 (-z/2 - x - 1) + z = 2.
x - 2 (-z/2 - x - 1) + z = x + (z + 2 x + 2) + z = 2 z + 3 x + 2:
{(13 z)/6 + (7 x)/3 + 1/3 = -1
y = -z/2 - x - 1
(2 z + 3 x + 2) = 2
STEP 7
Hint: | Choose an equation and a variable to solve for.
In the first equation, look to solve for x:
{(13 z)/6 + (7 x)/3 + 1/3 = -1
y = -z/2 - x - 1
2 z + 3 x + 2 = 2
STEP 8
Hint: | Isolate terms with x to the left hand side.
Subtract (13 z)/6 + 1/3 from both sides:
{(7 x)/3 = -(13 z)/6 - 4/3
y = -z/2 - x - 1
2 z + 3 x + 2 = 2
STEP 9
Hint: | Solve for x.
Multiply both sides by 3/7:
{x = -(13 z)/14 - 4/7
y = -z/2 - x - 1
2 z + 3 x + 2 = 2
STEP 10
Hint: | Perform a substitution.
Substitute x = -(13 z)/14 - 4/7 into the third equation:
{x = -(13 z)/14 - 4/7
y = -z/2 - x - 1
2 + 3 (-(13 z)/14 - 4/7) + 2 z = 2
STEP 11
Hint: | Expand the left hand side of the equation 2 + 3 (-(13 z)/14 - 4/7) + 2 z = 2.
2 + 3 (-(13 z)/14 - 4/7) + 2 z = 2 z + (-(39 z)/14 - 12/7) + 2 = -(11 z)/14 + 2/7:
{x = -(13 z)/14 - 4/7
y = -z/2 - x - 1
(-(11 z)/14 + 2/7) = 2
STEP 12
Hint: | Choose an equation and a variable to solve for.
In the third equation, look to solve for z:
{x = -(13 z)/14 - 4/7
y = -z/2 - x - 1
-(11 z)/14 + 2/7 = 2
STEP 13
Hint: | Isolate terms with z to the left hand side.
Subtract 2/7 from both sides:
{x = -(13 z)/14 - 4/7
y = -z/2 - x - 1
-(11 z)/14 = 12/7
STEP 14
Hint: | Solve for z.
Multiply both sides by -14/11:
{x = -(13 z)/14 - 4/7
y = -z/2 - x - 1
z = -24/11
STEP 15
Hint: | Perform a back substitution.
Substitute z = -24/11 into the first and second equations:
{x = 16/11
y = -x + 1/11
z = -24/11
STEP 16
Hint: | Perform a back substitution.
Substitute x = 16/11 into the second equation:
Answer: | 
 | {x = 16/11
y = -15/11
z = -24/11