Question

Find the value of m so that the quadratic equation mx(x-7)+49=0 has real and equal roots

Answer 1

Given :quadratic equation mx(x-7)+49=0

 To find :  the value of m so that quadratic equation has two equal roots.

=> mx(x-7)+49=0.....(1)

=> mx2 - 7mx +49 =0

it is a quadratic equation where a = m , b =-7m , c = 49

 For equal roots D =0

D = b2 - 4ac =0    => (-7m)2 - 4 (m)(49) =0     => 49m2 - 4 m(49) =0     => m2 -4m =0      => m (m-4) =0       => m =0 and m =4   Since m=0 is invalid here as by putting the value in the eq (1)   => 0 + 49 = is not equal to 0

Answer 2

heya it's Aastha....

◆mx( x-7)+49=0

◆mx^2 -7mx +49 =0

●on comparing equation with standard form

●a= m , b = -7m ,c = 49

◆D= b^2 - 4ac

0 = 49m^2 - 4× 49m

0 = 49 m^2 - 196m

196m= 49m^2

4 = m

m = 4

I hope it help you.