Please help!! I dont know where to start

If you were to use the substitution method to solve the following system, choose the new system of equations that would result if x was isolated in the second equation.

3x - 5y + z = 12
x + 6y - z = -4
2x - 5y - 2z = -8

Question

Please help!! I dont know where to start

If you were to use the substitution method to solve the following system, choose the new system of equations that would result if x was isolated in the second equation. 


3x - 5y + z = 12 
x + 6y - z = -4 
2x - 5y - 2z = -8

tkhunny · Answer

Have you considered solving one equation for a variable of your choice and substituting the result into the other two equations?

anonymous · Answer

Read the instructions, then follow along....  Isolate x in the second equation gives$$x =- 6y+ z -4$$then substitute....$$3x - 5y + z = 12 \implies 3(- 6y+ z -4) - 5y + z = 12$$$$2x - 5y - 2z = -8 \implies 2(- 6y+ z -4) - 5y - 2z = -8$$Simplify, and you have your system.