Answer to Question #178268 in Linear Algebra for sarang

Question #178268

Find the conditions on a, b, and c so that the following linear system of equations have a solution.

−2x + y + z = a

x − 2y + z = b

x + y − 3z = c


1
Expert's answer
2021-04-15T07:41:05-0400

Δ=2(61)1(31)+1(1+2)=10+4+3=30,\Delta=-2\cdot(6-1)-1\cdot(-3-1)+1\cdot(1+2)=-10+4+3=-3≠0,


Δ1=a(65)1(3bc)+1(b+2c)=a+4b+3c,\Delta_1=a\cdot(6-5)-1\cdot(-3b-c)+1\cdot(b+2c)=a+4b+3c,

Δ2=2(3bc)a(31)+1(cb)=4a+5b+3c,\Delta_2=-2\cdot(-3b-c)-a\cdot(-3-1)+1\cdot(c-b)=4a+5b+3c,

Δ3=2(2cb)1(cb)+a(1+2)=3a+3b+3c,\Delta_3=-2\cdot(-2c-b)-1\cdot(c-b)+a\cdot(1+2)=3a+3b+3c,


x=Δ1Δ=a343bc,x=\frac{\Delta_1}{\Delta}=-\frac a3-\frac 43 b-c,

y=Δ2Δ=43a53bc,y=\frac{\Delta_2}{\Delta}=-\frac 43 a-\frac 53 b-c,

z=Δ3Δ=abc,z=\frac{\Delta_3}{\Delta}=-a-b-c,


there is a solution for any a, b, c.


Need a fast expert's response?

Submit order

and get a quick answer at the best price

for any assignment or question with DETAILED EXPLANATIONS!

Comments

No comments. Be the first!

Leave a comment