Question

for what values of "t" the pair of linear equation 5x+2y+3=0 and 15x+6y+t=0 represents coincident lines

Answer 1

When line Coincident then ,

$\frac{a1}{a2} = \frac{b1}{b2} = \frac{c1}{c2}$
$\frac{ a1}{a2} = \frac{c1}{c2}$


$\frac{5}{15} = \frac{3}{t}$


9 = t

Answer 2

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