Question

Choose the correct answer from the given four options in the following questions:
If one of the zeroes of the quadratic polynomial (k-1) x² + k x + 1 is –3, then the
value of k is
4.
A 4/3
(B) -4/3
(C) ⅔
(D)-⅔​

Answer 1

Answer:

(A) 4/3

Step-by-step explanation:

-3 is zero of (k-1) x^2 +kx+1

now, (k-1) (-3) ^2 +k(-3) +1 =0

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

9k-9-3k+1 = 0

6k -8 = 0

6k = 8

k= 8/6

k=4/3

Answer 2

ANSWER:

Given:

• p(x) = (k - 1)x² + kx + 1
• -3 is a zero of p(x)

To Find:

• Value of k

Solution:

$\text{We are given that,}\\\\:\longrightarrow p(x)=(k-1)x^2+kx+1\\\\\text{We are also given that, -3 is a zero of p(x).}\\\\\text{So,}\\\\:\implies p(-3)=0\\\\\text{Hence,}\\\\:\implies p(-3)=(k-1)(-3)^2+k(-3)+1=0$

$:\implies9(k-1)-3k+1=0\\\\:\implies9k-9-3k+1=0\\\\:\implies9k-3k-9+1=0\\\\:\implies6k-8=0\\\\:\implies6k=8\\\\:\implies k=\dfrac{8\!\!\!/^{\:4}}{6\!\!\!/_{\:3}}\\\\\bf{:\implies k=\dfrac{4}{3}}\\\\\text{\bf{Hence, option A) \dfrac{4}{3} is the correct value of k.}}$