Question

if one root of quadratic equation kx2-14x+8 is 6 times the other find the value of k

Answer 1

Answer:

k=3

Explanation:

Let m,6m are two roots of

kx²-14x+8=0,

Compare this with ax²+bx+c=0

we get,

a=k,b=-14,c = 8

i) sum of the roots = -b/a

=> m+6m = -(-14)/k

=> 7m = 14/k

=> m = 14/7k

=> m = 2/k ---(1)

product of the roots = c/a

=> m×6m = 8/k

=>m²= 8/6k

=> m² = 4/3k ---(2)

=> (2/k)² = 4/3k [ from (1)]

=> 4/k² = 4/3k

=> (4×3)/4 = k

=> 3 = k

Therefore,

k = 3

••••

Answer 2

Hey!

Refer the below attachment !

Thanks !