Question

Which of the following is the solution of the given system of equations?

2x + 2y + z = -12

x + z = 20

x = 1

A) (1, -33/2, 19 )

B) ( 1, 33/2, 19)

C) (1, -17, 19)

D) (1, -25, 21)

Answer 1

The answer is A We have. x=1, then we substitute that on x+z = 20, to solve for z. 1+z=20 z=20-1 z=19 Then we substitute both values x=1 and z=19 on the other equation. 2x +2y+ z = -12 2*1 + 2y + 19= -12 2y= -12 -19-2 2y= -33 y=-33/2