Question

Tìm x biết

a, ( x - 2)² - (x - 3)​(x+3) = 6

b, 4( x - 3)² --(2x - 1)(2x + 1)= 10

c, ( x - 4)² - x (x -2(x + 2) = 6

d, 9( x + 1)^2 ​-(3x -2)(3x+ 2)= 10

Answer 1

a ) \(\left(x-2\right)^2-\left(x-3\right)\left(x+3\right)=6\)

\(\Leftrightarrow x^2-4x+4-x^2+9=6\)

\(\Leftrightarrow-4x+13=6\)

\(\Leftrightarrow-4x=-7\)

\(\Leftrightarrow x=\frac{7}{4}\)

Vậy \(x=1\).

b ) \(4\left(x-3\right)^2-\left(2x-1\right)\left(2x+1\right)=10\)

\(\Leftrightarrow4\left(x^2-6x+9\right)-\left(4x^2-1\right)=10\)

\(\Leftrightarrow4x^2-24x+36-4x^2+1=10\)

\(\Leftrightarrow-24x+37=10\)

\(\Leftrightarrow-24x=27\)

\(\Leftrightarrow x=\frac{9}{8}.\)

Mấy pài kia tương tự . :D

 

Answer 2

cậu khai triển các tích ra là ra thui mà cậu