If `2x+3y+z=55 ,\ \ x+z-y=4` and `y-x+z=12` , then what are the values of `x ,\ y` and `z` ?

2x = 3y = 4z, x: y: z

If 2x = 3y = 4z, find x:y: z.

If x(x+y+z)=9, y(x+y+z)=16 and z(x+y+z)=144 then what is the value of x?

If 2x+3y=31,backslash backslash y-z=4 and x+2z=11, then what is the value of x+y+z?( a )12 (b) 13 (c) 15 (d) 16

If 4 x^(2) + 9y^(2) + z^(2) + 49 = 12 ( x+ y + z) , then what is the value of (4x + 9y - z) ?

If x : y : z = 3 : 4 : 9, then what will be the value of (2x + 3y + z) : (2z + x – 3y)?