Question

Find the value of kx ^2 - 14x + 8 = 0 if one of the root is six times the other.

Answer 1

Answer:

3

Step-by-step explanation:

let x and y be the roots

they said x=6y

so

by formula of coefficients

x+y=14\k

7y=14\k

y=2\k

and we know

xy=8\k

6y^2=8\k

6 x 4\k^2=8\k

k=3

Answer 2

Answer:

Value of k is 3

Step-by-step explanation:

Let the roots be α,6α

As per quadratic rule we get,

Sum of roots= -b/a

Product of roots= c/a

α+6α=14

7α=14/k

α=2/k

α^2=4/k^2

6α(α)=8/k

6α^2=8/k

α^2=4/3k

4/k^2=4/3k

1/k^2=1/3k

k^2=3k

k=3