Question

Find the value of k , in quadratic equations
$9x -kx + 16 = 0$
it roots are equal.​

Answer 1

Condition for roots to be equal in a quadratic equation is ,

• Discriminant = D = 0

Here , D = b²-4ac = ( -k )² - 4 (9)(16) = 0

=> k² = 4×9×16

=> k = √ ( 4×9×16) = 2×3×4

=> k = 24

==> Value of k , in quadratic equation 9x² - kx +16 = 0 , for its roots to be equal is , 24.