Question

1
one zero of the quadratic polynomial (K-1) x ² + Kx + 1 is -3

find value of k

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Answer 1

• x= -3
• (k -1)x²+kx+1= 0
• (k-1)(-3)²+k(-3)+1=0
• (k-1)(9)-3k+1=0
• 9k-9-3k+1=0
• 9k-3k-9+1=0
• 6k-8=0
• 6k=8
• k=8/6
• k=4/3.

hope this will help you to understand

Answer 2

f(x) = (K-1) x ² + Kx + 1

f(3) = 0

(K-1) (-3 )² + K(-3 )+ 1 = 0

9(k-1)-3k+1= 0

9k-9-3k+1= 0

6k-8 =0

k= 8/6

k= 4/3