Toán Lớp 6: (3x+6).x=0 (8+2x).(x-3)=0 (2+x)^2=16

Question

Toán Lớp 6:  (3x+6).x=0 (8+2x).(x-3)=0 (2+x)^2=16

thienthanh · Answer

( 3x + 6 ) . x = 0     &hArr;  ( left[  begin{array}{l}3x+6=0  x=0 end{array}  right. )      &hArr;  ( left[  begin{array}{l}3x=-6  x=0 end{array}  right. )      &hArr;  ( left[  begin{array}{l}x=-6:3  x=0 end{array}  right. )      &hArr;  ( left[  begin{array}{l}x=-2  x=0 end{array}  right. )      Vậy x = - 2 ; x = 0     ( 8 + 2x ) . ( x - 3 ) = 0     &hArr;  ( left[  begin{array}{l}8+2x=0  x-3=0 end{array}  right. )      &hArr;  ( left[  begin{array}{l}2x=-8  x=3 end{array}  right. )      &hArr;  ( left[  begin{array}{l}x=-8:2  x=3 end{array}  right. )      &hArr;  ( left[  begin{array}{l}x=-4  x=3 end{array}  right. )      Vậy x = - 4 ; x = 3     ( 2 + x )^2 = 16     &hArr; 2 + x = &plusmn; 4     &hArr;  ( left[  begin{array}{l}2+x=4  2+x=-4 end{array}  right. )      &hArr;  ( left[  begin{array}{l}x=4-2  x=-4-2 end{array}  right. )      &hArr;  ( left[  begin{array}{l}x=2  x=-6 end{array}  right. )      Vậy x = 2 ; x = - 6

trucoanh55 · Answer

Giải đáp+Lời giải và giải thích chi tiết:    (3x+6).x=0   =>[(3x+6=0),(x=0):}   =>[(3x=-6),(x=0):}   =>[(x=-2),(x=0):}   Vậy x&isin;{-2;0}   __________________________    (8+2x).(x-3)=0   =>[(8+2x=0),(x-3=0):}   =>[(2x=-8),(x=3):}   =>[(x=-4),(x=3):}   Vậy x&isin;{-4;3}   __________________________    (2+x)^2=16   =>(2+x)^2=4^2 hoặc (2+x)^2=(-4)^2   =>2+x=4 hoặc 2+x=-4   =>x=2 hoặc x=-6   Vậy x&isin;{-6;2}