Q:

How do I find X Y and Z using these equations: 2x-y+2z=7 -x+2y-2z=-6 and -2x+3y-4z=-9 ?​

Accepted Solution

A:
Answer:x=4/5, y=1/5, z=14/5orusing decimalsx=0.8,  y=0.2,  z= 2.8Step-by-step explanation:2x-y+2z=7 (1)-x+2y-2z=-6 (2)2x+3y-4z=-9 (3)1) Add equations (1) and (2)2x-y+2z=7 -x+2y-2z= - 6x + y     =  1  (equation 5)2) Multiply equation (2) by - 2 -x+2y-2z= - 6 / *(-2)2x  - 4y+4z = 12     (equation 4)3) add equation (4) and (3)2x  - 4y+4z = 12 2x   +3y -4z= - 9 4x - y  =         3 (equation 6)4) Add equation (5) and equation (6) to find xx + y     =  1 4x - y  =  3 5x      = 4x = 4/55) Use equation 5 to find yx+y = 1,  x=4/54/5+y=1y=1/56) Use equation (1) to find z2x-y+2z=7 , x=4/5, y=1/52*4/5 - 1/5 +2z =78/5-1/5 +2z = 77/5 + 2z = 72z = 7- 7/52z = 35/5 - 7/52z = 28/5z =14/5