Question

find the value of k if 2x-4y+7=0 and10x+20y+k=0 are coincident
plz find the answer fast​

Answer 1

Question-

• Find the value of k if 2x-4y+7=0 and

10x +20y+k =0 are coincident

Solution -

$2x - 4y + 7 = 0$

And,

$10x + 20y + k = 0$

For the lines to be coincident,

$\frac{ a_{1}}{ b_{1} } = \frac{ a_{2} }{ b_{2} } = \frac{ a_{3} }{ a_{3} }$

Here,

$a_{1} = 2$

$b_{1} = 10$

$a_{2} = - 4$

$b_{2} = 20$

$a_{3} = 7$

$a_{3} = k$

So,

As the line is coincident it has indefinitely many solutions

$\frac{2}{10} = \frac{ - 4}{20} = \frac{7}{k}$

$\implies \frac{2}{10} = \frac{7}{k}$

$\implies2k = 70$

$\implies \: k = \frac{70}{2}$

$\implies \: k = 35$