Question

Solve

(x2-4x)(x2-4x-1)-20

Answer 1

HEY!!

(x2 4x) (x2 4x 1) 20

Putx2 4x=t

= (x2 4x) (x2 4x 1) 20 =t(t 1) 20 =t2t 20 =t2 5t+ 4t 20

=t(t 5) + 4 (t 5) = (t+ 4) (t 5)

= (x2 4x+ 4) (x2 4x 5)

= (x2 2x 2x+ 4) (x2 5x+x 5)

= [x(x 2) 2 (x 2)] [x(x 5) + 1 (x 5)]

= (x 2) (x 2) (x+ 1) (x 5)

Answer 2

$( {x}^{2} - 4x)( {x}^{2} - 4x - 1) - 20 \\ = m(m - 1) - 20 \\ = {m}^{2} - m - 20 \\ = {m }^{2} - 5m + 4m - 20 \\ = m(m - 5) + 4(m - 5) \\ = (m - 5) (m + 4) \\ = ( {x}^{2} - 4x - 5)( {x}^{2} - 4x + 4) \\ = ( {x}^{2} - 5x + x - 5)( {x}^{2} - 2x - 2x + 4) \\ = {x(x - 5) + 1(x - 5)}{x(x - 2) - 2(x - 2)} \\ = (x - 5)(x + 1)(x - 2)(x - 2)$
Hey dear here is your answer

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hope it helps you ✌️