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.

2x + 5y – 2z = –1
x + 3y + z = –2
3x – 2y + 3z = –17

Choices:

A)–y = –5
6x + 7y = –11

B)11y = 3
7y + 6z = –11

C)4x + 11y = –5
–11y = –11

D)–y – 4z = 3
–11y = –11

Please help

Question

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.

2x + 5y – 2z = –1
x + 3y + z = –2
3x – 2y + 3z = –17

Choices:

A)–y = –5
6x + 7y = –11
		
B)11y = 3
7y + 6z = –11
	
C)4x + 11y = –5
–11y = –11
		
D)–y – 4z = 3
–11y = –11

Please help

anonymous · Answer

Isolate x in the second equation.
Then plug it into the first equation, foil and solve.
Then plug it into the second equation, foil and solve.

anonymous · Answer

so is the the answer or just the first equation being foiled?

anonymous · Answer

x = -3y -z -2

anonymous · Answer

then...
for the first...
2(-3y-z-2) +5y -2z = -1

anonymous · Answer

and 
for the second...
3(-3y-z-2) -2y +3z = -17

anonymous · Answer

so they just solve for x in the second equation and plug it right into the other eq1 and eq3

anonymous · Answer

then foil and combine like terms..

anonymous · Answer

oh ok thanks for the help :)

anonymous · Answer

so would the answer be D?