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Can you manipulate the coefficients of any variable terms such that they could be eliminated?
(-3,1,-1)
The given system consists of equations of planes. Notice that the coefficient of c in the first equation is the additive inverse of the coefficient of c in the second equation; they will add to be 0. Let's use the Elimination Method to find a solution to this system. a+b + c=-3 & (I) 3b - c=4 & (II) 2a-b-2c=-5 & (III) We can start by adding the first equation to the second equation to eliminate the c-terms.
(II): Add (I)
(II): Remove parentheses
(II): Add and subtract terms
Having eliminated the c-variable from the second equation, we can continue by creating additive inverse coefficients for c in the first and second equations. Then, we can add or subtract these equations to eliminate c from the third equation.
(I): LHS * 2=RHS* 2
(III): Add (I)
(III): Remove parentheses
(III): Add and subtract terms
(II): LHS * (-4)=RHS* (-4)
(II): Add (III)
(II): Add and subtract terms
(II): .LHS /(-15).=.RHS /(-15).
Now that we know that b=1, we can substitute it into the third equation to find the value of a.
The value of a is -3. Let's substitute both values into the first equation to find c.
The solution to the system is ( -3, 1, -1). 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.