Question

Tim x thuoc so nguyen,biet:

a. (x+1).(x-2)=0

b.10+3(x-1)=10+6x

c. x-96=(9443-x)-15

Answer 1

a, ( x + 1 ). ( x - 2 ) = 0

\(\Rightarrow\orbr{\begin{cases}x+1=0\\x-2=0\end{cases}\Leftrightarrow\orbr{\begin{cases}x=0-1\\x=0+2\end{cases}\Leftrightarrow}\orbr{\begin{cases}x=-1\\x=2\end{cases}}}\)

Vậy x = { -1 ; 2 }

b, 10 + 3( x-1 ) = 10 + 6x

=> 10 + 3x - 3 = 10 + 6x

=> 10 - 3 + 3x = 10 + 6x

=> 7 + 3x = 10 + 6x

=> 3x - 6x = 10 - 7

=> -3x = 3

=> x = 1

 Vậy x = 1 

c, x - 96 = ( 9443 - x ) -15

=> x - 96 = 9443 - x - 15

=> x - 96 = 9443 - 15 - x 

=> x - 96 = 9428 - x 

=> x + x = 9428 + 96

=> 2x = 9524

=> x = 4762

 Vậy x = 4762