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Can you manipulate the coefficients of any variable terms such that they could be eliminated?
(4,2,-3)
The given system consists of equations of planes. Notice that the coefficients of y in the first and the third equations are the additive inverse of the coefficient of y in the second equation; they will add to be 0. Let's use the Elimination Method to find a solution to this system. x - y+z=-1 & (I) x + y+3z=-3 & (II) 2x - y+2z=0 & (III) We can start by adding the second equation to the first and the third equations to eliminate the y-terms.
(I), (III): Add (II)
(I), (III): Remove parentheses
(I), (III): Add and subtract terms
Next, we will use our two equations that are only in terms of x and z to solve for the value of one of the variables. We will once again apply the Elimination Method, but this time it will be similar to when using it in a system with only two variables.
(I): LHS * (-3)=RHS* (-3)
(III):LHS * 2=RHS* 2
(III): Add (I)
(III): Remove parentheses
(III): Add and subtract terms
(III): .LHS /(-2).=.RHS /(-2).
Now that we know that z=-3, we can substitute it into the first equation to find the value of x.
(I): z= -3
(I): - a(- b)=a* b
(I): LHS-36=RHS-36
(I): .LHS /(-6).=.RHS /(-6).
The value of x is 4. Let's substitute both values into the second equation to find y.
(II): x= 4, z= -3
(II): a(- b)=- a * b
(II): Subtract term
(II): LHS+5=RHS+5
The solution to the system is ( 4, 2, -3). This is the singular point at which all three planes intersect. Now we can check our solution by substituting the values into the system.
(I), (II), (III): Substitute values
(I), (II), (III): Multiply
(I), (II), (III): Add and subtract terms
Since the substitution of our answers into the given equations resulted in three identities, we know that our solution is correct.