Question

x=3 is a root of the quadratic equation 7x2-(k+1)+3=0 if k=?​

Answer 1

Answer:

$p(x)=7x^2-(k+1)x+3=0$

$p(3)=7(3)^2-(k+1)*3+3=0$

$7(9)-3k-3+3=0$

$63-3k=0$

$-3k=-63$

$3k=63$

$k=63/3$

$k=21$

Answer 2

Answer:

Given Quadratic equation: 7x² - (k+1) + 3 = 0.

Given that x =3 is a root of the equation.

So, x= 3 will satisfy the equation.

Therefore,

7×(3²) - k - 1 + 3 = 0

=> 63 - k + 2 = 0

=> k = 65.

so, your required answer is 65.

Hope it helps!!!