Question

Giúp tớ với. Cần gấp luôn đấy

Tìm x

( x - 2 )^2 - ( x + 3 )^2 - 4( x + 1 ) = 5

( x + 3 )^2 - ( x - 2 )( x + 2 )- 2( x - 1 )^2 = 7

 ( 2x - 3 )( 2x + 3 ) - ( x - 1 )^2 - 3x( x - 5 ) = -44

Làm đúng tớ đi.... đúng tick liền 

 

 

Answer 1

a) \(\left(x-2\right)^2-\left(x+3\right)^2-4\left(x+1\right)=5\)

\(\Leftrightarrow x^2-4x+4-\left(x^2+6x+9\right)-4x-4=5\)

\(\Leftrightarrow x^2-4x+4-x^2-6x-9-4x-4=5\)

\(\Leftrightarrow-14x=14\)

\(\Leftrightarrow x=-1\)

b) \(\left(2x-3\right)\left(2x+3\right)-\left(x-1\right)^2-3x\left(x-5\right)=-44\)

\(\Leftrightarrow4x^2-9-x^2+2x-1-3x^2+15x=-44\)

\(\Leftrightarrow17x=-34\Rightarrow x=-2\)