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The pair of linear equations 2x+3y=8 and 4x+6y=16 have:
Exactly one solution
No solution
Infinitely many solutions
Two distinct solutions
Infinitely many solutions
Check if the second equation is an exact multiple of the first by comparing the ratios of coefficients.
Equations: 2x + 3y = 8 and 4x + 6y = 16
╬Ф=тАЛ24тАЛ36тАЛтАЛ=0
Check if the second equation is an exact multiple of the first by comparing the ratios of coefficients.
Assuming a unique solution without testing for proportional coefficients leads to a wrong answer.
Identify proportionality
Observe that the coefficients of the second equation are exactly twice those of the first: 4=2├Ч2, 6=2├Ч3, 16=2├Ч8.
4=2├Ч2,6=2├Ч3,16=2├Ч8
Compute determinant
For a system ax+by=c and dx+ey=f, the determinant ╬Ф=aeтИТbd tells if the lines are parallel (╬Ф=0) or intersecting (╬ФюАа=0). Here a=2, b=3, d=4, e=6.
╬Ф=2├Ч6тИТ3├Ч4=12тИТ12=0
Conclude nature of solutions
Since ╬Ф=0 and the constant terms are also in the same ratio (16 = 2├Ч8), the equations represent the same line, giving infinitely many solutions.
Infinite┬аsolutions┬аbecause┬аthe┬аequations┬аare┬аdependent
C is correct because the two equations are proportional, representing the same line and thus have infinitely many solutions.
In matrix form, a zero determinant indicates rank deficiency; similar checks are used for solving linear equations in higher dimensions.