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Can you manipulate the coefficients of any variable terms such that they could be eliminated?
(2,-1,1)
The given system consists of equations of planes. Notice that the coefficient of z in the first equation is the additive inverse of the coefficient of z in the third equation; they will add to be 0. Let's use the Elimination Method to find a solution to this system. x+4y- 5z=-7 & (I) 3x+2y+3z=7 & (II) 2x+y+ 5z=8 & (III) We can start by adding the third equation to the first equation to eliminate the z-terms.
(I): Add (III)
(I): Add terms
Having eliminated the z-variable from the first equation, we can continue by creating additive inverse coefficients for z in the second and third equations. Then we can add or subtract these equations to eliminate z from the second equation.
(II): LHS * 5=RHS* 5
(III): LHS * 3=RHS* 3
(II): Subtract (III)
(II): Distribute -1
(II): Subtract terms
Now that we know that y=-1, we can substitute it into the first equation to find the value of x.
(I): y= -1
The value of x is 2. Let's substitute both values into the third equation to find z.
The solution to the system is ( 2, -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.