Question

What is the value of K, if one root of the quadratic equation Kx² - 7x + 12 =0 is 3 ?​

Answer 1

Answer:

k(x)2-7x+12=0

k(3)2-7×3+12=0

k9-21+12=0

k9-9=0

k=0

Answer 2

Answer:

kx² - 7x + 12 = 0

Where

3 is one root of the quadratic equation :- kx² - 7x + 12 = 0

So

x =3 is satisfied the equation

Now

put the value of x on given quadratic polynomial

We get

=> k × ( 3 ) ² - 7 × 3 + 12 = 0

=> k × 9 - 21 + 12 = 0

=> 9k - 9 = 0

=> 9k = 9

=> k = 9/9

=> k = 1

So, value of k = 1