Làm giùm điiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii Question Làm giùm điiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii in progress 0 Môn Toán Phúc Điền 9 months 2021-04-23T13:23:38+00:00 2021-04-23T13:23:38+00:00 2 Answers 3 views 0
Answers ( )
a) 3 1/2 – 1/2x = 2/3
⇔7/2 – 1/2x = 2/3
⇔1/2x = 7/2 – 2/3
⇔1/2x = 21/6 – 2/6
⇔1/2x = 19/6
⇔x = 19/6 : 1/2
⇔x = 19/6 x 2
⇔x = 19/3
b) 1/3 + 2/3 : x = -7
⇔2/3 : x = -7 – 1/3
⇔2/3 : x = -21/3 – 1/3
⇔2/3 : x = -22/3
⇔x = 2/3 : -22/3
⇔x = 2/3 x 3/-22
⇔x = -1/11
d) (2x – 3)(6 – 2x) = 0
⇔[2x-3 = 0
[6-2x=0
⇔[2x=0+3
[2x=2-0
⇔[2x=3
[2x=6
⇔[x=3:2
[x=6:2
⇔[x=3/2
[x=3
*Lời giải :
`a) 3 1/2 – 1/2x = 2/3`
`-> 7/2 – 1/2x = 2/3`
`-> 1/2x = 7/2 – 2/3`
`-> 1/2x = 17/6`
`-> x = 17/6 : 1/2`
`-> x = 17/3`
Vậy `x = 17/3`
`b) 1/3 + 2/3 😡 = -7`
`-> 2/3 : x = -7 – 1/3`
`-> 2/3 : x = (-22)/3`
`-> x = 2/3 : (-22)/3`
`-> x = (-1)/11`
Vậy `x = (-1)/11`
`c) 1/3x + 2/5 (x – 1) = 0`
`-> 1/3x + 2/5x – 2/5 = 0`
`-> (1/3 + 2/5) . x = 0 + 2/5`
`-> 11/15x = 2/5`
`-> x = 2/5 : 11/15`
`-> x = 6/11`
Vậy `x = 6/11`
`d) (2x – 3) (6 – 2x) = 0`
`->` \(\left[ \begin{array}{l}2x-3=0\\6-2x=0\end{array} \right.\)
`->` \(\left[ \begin{array}{l}2x=3\\2x=6\end{array} \right.\)
`->` \(\left[ \begin{array}{l}x=\dfrac{3}{2}\\x=3\end{array} \right.\)
Vậy `x= 3/2` hoặc `x = 3`