Question

x² - 21x + 38

Answer 1

\(x^2-21x+38\\ =\left(x^2-2x\right)-\left(19x-38\right)\\ =x\left(x-2\right)-19\left(x-2\right)\\ =\left(x-2\right)\left(x-19\right)\)

Answer 2

`x^{2}-21x+38=(x^{2}-2x)-(19x-38)`

`=x(x-2)-19(x-2)`

`=(x-2)(x-19)`

Answer 3

Đề bài 
= \(\left(x^2-2x\right)-\left(19x-38\right) \)
=\(x\left(x-2\right)-19\left(x-2\right)\)
=\(\left(x-2\right)\left(x-19\right)\)