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 first equation.
x + 6y + z = 2
x – 3y + 2z = –1
x + 5y + 3z = –4

a. 11y + 4z = 6
2y + 5z = 3

b. y – 2z = 6
–8y – z = 3

c. –9y + z = –3
–y + 2z = –6

d. 3y + 3z = –3
11y + 4z = –6

Answer 1

option C

the 3 equations
x + 6y + z = 2 (1)
x - 3y + 2z = -1 (2)
x +5y +3z = -4 (3)

Equation (2) - (1) Equation (3) - (1)

x - 3y + 2z = -1 x + 5y + 3z = -4
- ( x + 6y + z = 2) - (x + 6y + z = 2)
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-9y + z = -3 -y + 2z = -6

Answer 2

hope it helps