mình gửi lộn
b) 17x – ( -16x – 37) = 2x + 43
-> 33x +37 =2x +43
->31x=6
-> x= 6/31
c) -2x –3. (x – 17) = 34 – 2(-x + 25)
->-5x + 51= 2x-16
->7x= 67
x= 67/7
d) (-x - 6) (x + 9) = 0
Ta có (-x-6)= 0 hoặc (x+9)=0
-> x=-6 hoặc x=-9
b) 17x – ( -16x – 37) = 2x + 43
\(\Leftrightarrow\)17x+16x+37=2x+43
\(\Leftrightarrow\)33x+37-2x-43=0
\(\Leftrightarrow\)31x=6
\(\Leftrightarrow\)x=31/6
c) -2x –3. (x – 17) = 34 – 2(-x + 25)
\(\Leftrightarrow\)-2x-3x-51=34+2x-50
\(\Leftrightarrow\)-5x-51=-16+2x
\(\Leftrightarrow\)-5x-51+16-2x=0
\(\Leftrightarrow\)-7x=35
\(\Leftrightarrow\)x=-5
d) (-x - 6) (x + 9) = 0
\(\hept{\frac{-x-6=0}{x+9=0}}\Leftrightarrow\)\(\hept{\begin{cases}x=-6\\x=-9\end{cases}}\)
Trả lời:
b, 17x - ( - 16x - 37 ) = 2x + 43
=> 17x + 16x + 37 = 2x + 43
=> 33x + 37 = 2x + 43
=> 33x - 2x = 43 - 37
=> 31x = 6
=> x = 6/31
Vậy x = 6/31
c, - 2x - 3 ( x - 17 ) = 34 - 2 ( - x + 25 )
=> - 2x - 3x + 51 = 34 + 2x - 50
=> - 5x + 51 = -16 + 2x
=> -5x - 2x = -16 - 51
=> -7x = -67
=> x = 67/7
Vậy x = 67/7
d, ( - x - 6 ) ( x + 9 ) = 0
=> - x - 6 = 0 hoặc x + 9 = 0
=> - x = 6 x= -9
=> x = -6
Vậy x = -6; x = -9