Question

what is value of K for which 3 is root of equation kx sauare minus 7x+3=0​

Answer 1

Answer

If x=3 is a root of the equation, then we know that (x−3) is a factor of the equation, thus:

kx2−7x+3=(x−3)(ax+b)=ax2−(b+3a)x−3b

Equating coefficients, we have:

x2: k=a

x:−7=b−3a→a=b+73

3=−3b→b=−1

Using 3. to substitute for b in 2., we have:

a=−1+73=2

From 1., we thus know that k=2

Explanation:

hope it will help you

Answer 2

Answer: k=2

Explanation: p(x)=kx^2-7x+3

since 3 is a root of p(x)

therefore,

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

k(9)-21+3=0

9k-18=0

9k=18

k=18/9

k=2