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Can you manipulate the coefficients of any variable terms such that they could be eliminated?
(-2,-1,12)
The given system consists of equations of planes. Let's use the Elimination Method to find a solution to this system. Notice that in the third equation there is no c-term.
4a+2b+c=2 & (I) 5a-3b+2c=17 & (II) a-5b=3 & (III)
Currently, none of the terms in this system will cancel out. However, if we multiply (I) by -2 the coefficient of c in this equation will be the additive inverse of the coefficient of c in the second equation; they will add to be 0.
-2(4a+2b+c)=-2(2) 5a-3b+2c=17 a-5b=3
⇓
-8a-4b - 2c=-4 5a-3b + 2c=17 a-5b=3
We can start by adding the second equation to the first equation to eliminate the c-terms.
(I): Add (II)
(I): Remove parentheses
(I): Add and subtract terms
Next, we will use our two equations that are only in terms of a and b 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.
(III): LHS * 3=RHS* 3
(III): Add (I)
(III): Remove parentheses
(III): Add and subtract terms
(III): .LHS /(-22).=.RHS /(-22).
Now that we know that b=-1, we can substitute it into the first equation to find the value of a.
(I): b= -1
(I): - a(- b)=a* b
(I): LHS-7=RHS-7
(I): .LHS /(-3).=.RHS /(-3).
The value of a is -2. Let's substitute the value of a and b into the second equation to find c.
The solution to the system is (-2,-1,12). This is the singular point at which all three planes intersect.