For what value of C, the following system of linear equations has infinite number of solution: Cx+

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05 Jun 2013 Linear Equation

For what value of C, the following system of linear equations has infinite number of solution:
Cx+3y-(C-3)=0 and 12x+Cy-C=0

OPtion

1) 1
2) 2
3) 3
4) 4
5) 5
6) 6
7) 7
8) 8
9) 9
10) None of these

Solution

For Infinite number of solutions:
C/12=3/C=-(C-3)/-C
From first two
C^2=36 and from last two 3=C-3
Common solution is 6
option 6

Correct Option: 6 Best Solution (9)

shivendra pratap singh   11 years AGO

for infinite number of solution: a1/a2=b1/b2=c1/c2
c/12=3/c=c-3/c
by solving we get :
c=6
so option 6)6 is correct one

Like? Yes (9) | No (2)  

Dr.Dipin Singh   11 years AGO

For infinite solutions

C/12 = 3/C = (C-3)/C

solving these eqns, we get
C=6 .. option 6

Like? Yes (7) | No (2)  

IFFAT IRAM   11 years AGO

for linear equations having infinite no. of solutions,
the ratio of the coefficients of variables of the eq are same...
C/12 = 3/C = (C-3)/C
now,
C/12=3/C
C^2 = 36
C=6
option 6

Like? Yes (5) | No (1)  

Satyaranjan   11 years AGO

Two equations have infinite solution if they have equal slopes.
So for first eq m1= -c/3
for second eq m2= -12/c
m1=m2
So we get c=6

Like? Yes (4) | No   

Jalay Shukla   11 years AGO

take determinant of first two terms of each equation.
and for infinite solution that should be zero.
so 6 is the answer

Like? Yes (3) | No (1)  

vinod   11 years AGO

substitute c=6
gives both equations same which results in infinite solutions

Like? Yes (3) | No (1)  

Balakrishnan M   11 years AGO

Cx+3y-(C-3)=0 and 12x+Cy-C=0
(C/12)=(3/C)=(C-3/C)
Equating first two,
c^2 = 36
c=6

Like? Yes (4) | No (2)  

sanjay singh   11 years AGO

for many solutions
c/12=3/c=-(c-3)/-c
solving we get c=6 or -6
but -6 do not satisfy
so 6 is the solution

Like? Yes (3) | No (1)  

Vinay Sipani    11 years AGO

(Cx + 3y) = (C - 3) -------(1)
12x + Cy = ( C ) -------(2)

determinant of
| C 3 | = 0
| 12 C |

=> C = 6

Like? Yes (3) | No (2)