If you were to use the elimination method to solve the following system, choose the new system of equations that would result after the variable z is eliminated in the first and second equations, then the second and third equations.

3x - 7y - z = -14
3x + 3y + 2z = 1
2x + 5y - 2z = -16

A)3x - 7y = -14
2x + 5y = -16

B)9x - 11y = -27
5x + 8y = -15

C)9x - 11y = -27
3x - 7y = -14

D)2x + 5y = -16
5x + 8y = -15

Question

If you were to use the elimination method to solve the following system, choose the new system of equations that would result after the variable z is eliminated in the first and second equations, then the second and third equations.

3x - 7y - z = -14
3x + 3y + 2z = 1
2x + 5y - 2z = -16
 	
	A)3x - 7y = -14
          2x + 5y = -16
	
       B)9x - 11y = -27
         5x + 8y = -15
	
       C)9x - 11y = -27
          3x - 7y = -14
	
        D)2x + 5y = -16
          5x + 8y = -15

anonymous · Answer

B

mathstudent55 · Answer

For the first two eqs, multiply the first one by 2 and add them.
For the last two eqs., just add them.
What do you get?