If x(x + y + z) = 20, y = (x + y + z) = 30 & z(x + y + z) = 50, then the value of 2(x + y + z) is?

A. 20

B. 10

C. 15

D. 18

Answer: Option A

Solution(By Examveda Team)

$$\eqalign{ & {\text{Put }}\left( {x + y + z} \right) = 10 \cr & x = 2 \cr & y = 3 \cr & z = 5 \cr & x\left( {x + y + z} \right) = 20 \cr & \Leftrightarrow 2\left( {10} \right) = 20 \cr & \Leftrightarrow 20 = 20 \cr & {\text{Similarly other will satisfied,}} \cr & {\text{So, value of 2}}\left( {x + y + z} \right) \cr & = 2\left( {10} \right) \cr & = 20 \cr} $$