Question
The equation $$x + 2y + 2z = 1{\text{ and }}2x + 4y + 4z = 9{\text{ have}}$$
A.
Only one solution
B.
Only two solutions
C.
Infinite number of solutions
D.
None of these
Answer :
None of these
Solution :
The given equations are
$$\eqalign{
& x + 2y + 2z = 1\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,.....\left( 1 \right) \cr
& {\text{and }}2x + 4y + 4z = 9\,\,\,\,.....\left( 2 \right) \cr
& {\text{Subtracting }}\left( 1 \right) \times \left( 2 \right){\text{from}}\left( 2 \right),{\text{ we get 0}} = {\text{7}} \cr
& \left( {{\text{not possible}}} \right) \cr
& \therefore {\text{ No solution}}{\text{.}} \cr} $$