Toán Tìm số nguyên x : -2x+3.{12-2[3x-(20+2x)-4x]+1}=45 06/12/2021 By Raelynn Tìm số nguyên x : -2x+3.{12-2[3x-(20+2x)-4x]+1}=45
-2x + 3.{12 – 2[3x -(20 + 2x)- 4x]+ 1}=45 ⇔-2x + 3.{12 – 2[3x – 20 – 2x- 4x]+ 1}=45 ⇔-2x + 3.{12 – 2[-20-3x]+ 1}=45 ⇔-2x + 3.{12 +40+6x+ 1}=45 ⇔-2x + 36 + 18x + 3 =45 ⇔ -2x+18x = 45- 3-120 – 36 ⇔16x = -114 ⇔x = -114 :16 ⇔x = -7,125 Vậy x = -7,125 Reply
Đáp án: `x=(-57)/8` Giải thích các bước giải: `-2x+3.{12-2[3x-(20+2x)-4x]+1}=45` `-2x+3{12-2[3x-20-2x-4x]+1}=45` `-2x+3{12-2[-3x-20]+1}=45` `-2x+3{12+6x+40+1}=45` `-2x+3(6x+53)=45` `-2x+18x+159=45` `16x=-114` `x=(-57)/8` Reply
-2x + 3.{12 – 2[3x -(20 + 2x)- 4x]+ 1}=45
⇔-2x + 3.{12 – 2[3x – 20 – 2x- 4x]+ 1}=45
⇔-2x + 3.{12 – 2[-20-3x]+ 1}=45
⇔-2x + 3.{12 +40+6x+ 1}=45
⇔-2x + 36 + 18x + 3 =45
⇔ -2x+18x = 45- 3-120 – 36
⇔16x = -114
⇔x = -114 :16
⇔x = -7,125
Vậy x = -7,125
Đáp án: `x=(-57)/8`
Giải thích các bước giải:
`-2x+3.{12-2[3x-(20+2x)-4x]+1}=45`
`-2x+3{12-2[3x-20-2x-4x]+1}=45`
`-2x+3{12-2[-3x-20]+1}=45`
`-2x+3{12+6x+40+1}=45`
`-2x+3(6x+53)=45`
`-2x+18x+159=45`
`16x=-114`
`x=(-57)/8`