Question

If the zeroes of the polynomial 4xsquare minus 8kx plus 9 is 4 .Find the value of k

Answer 1

Answer:

K=73/32

Step-by-step explanation:

$4 {x}^{2} - 8kx + 9 = 0 \\ if \: x = 4 \: is \: a \: root \: of \: ths \: equation \: then \\ 4( {4)}^{2} - 8(4)k + 9 = 0 \\ 64 - 32k + 9 = 32k = 73 \\ k = \frac{73}{32}$

Answer 2

$\huge\star{\green{\underline{\mathfrak{Answer :-}}}}$

Zero of the polynomial = 4.

Polynomial = $\sf{4{x}^{2}-8kx+9}$.

Find the value of = k.

$\rule{200}2$

Putting the value of x that is the zero of the polynomial in the polynomial,

$\mapsto\sf{4{(4)}^{2}-8k(4)+9=0}$

$\mapsto\sf{4(16)-32k+9=0}$

$\mapsto\sf{64-32k+9=0}$

$\mapsto\sf{73-32k=0}$

$\mapsto\sf{-32k=-73}$

$\mapsto\sf{k=\dfrac{-73}{-32}}$

$\mapsto\huge{\underline{\sf{k=2.281}}}$

$\rule{200}2$

Checking if the answer is correct:-

$\mapsto\sf{-32k=-73}$

$\mapsto\sf{-32(2.281)=-73}$

$\mapsto\underline{\sf{-72.992\approx-73}}$

$\rule{200}4$