Answer:
x = 0, y = 1.333, z = -1.667 ( to the nearest thousandth).
Step-by-step explanation:
2x – 3y - 9z = 11 A
3x + 3z= – 5 B
-3x + y - 4z = 8 C
Multiply Equation C by 3:
-9x + 3y - 12z = 24 D
Adding A + D:
-7x - 21z = 35 Divide by 7:
-x - 3z = 5 E
Adding B + E:
2x = 0
x = 0
Plugging in x = 0 into equation B:
3(0) + 3z = -5
z = -5/3
z = -1 .667
Now plugging the values of y and z into equation A:
2(0) - 3y - 9(-5/3) = 11
-3y = 0 + 11 + 9(-5/3) = -4
y = 4/3 = 1.333.
Answer:
Step-by-step explanation:
2x – 3y - 9z = 11 ... (1)
3x + 3z= – 5 ....(2)
-3x + y - 4z = 8 ....(3)
add (3) and (2) : y - z = 3 so : y = z+3 (*)
put this value in (1) : 2x-3(z+3) -9z = 11
2x-3z -9-9z = 11 so : 2x =12z+20
x = 6z+10 ....(**)
put this value in (2) : 3(6z+10)+3z = -5
18z+30+3z=-5
21z = -35
z = -35/21= - 5/3
put this value in (*) and (**) you have x and y .
