-45 : 5.( -3 - 2x) = 3
-45:5.(-3-2x)=3
`-45 : 5 . ( -3 - 2x ) = 3`
`5 . ( -3 - 2x ) = -45 : 3`
`5 . ( -3 - 2x ) = -15`
`-3 - 2x = -15 : 5`
`-3 - 2x = -3`
`-2x = -3 + 3`
`-2x = 0`
`x = 0`
−45:5.(−3−2x)=3
5.(−3−2x)=−45:3
5.(−3−2x)=−15
−3−2x=−15:5
−3−2x=−3
−2x=−3+3
−2x=0
x=0
1/ (2x - 5) +17 =6
2/ 10 - 2(4 - 3x) = - 4
3/- 12 +3(- x + 7) = -18
4/ 24 :(3x - 2)= - 3
5/ - 45 :5.(- 3- 2x) = 3
\(\text{1/ (2x - 5) +17 =6}\\ 2x-5=6-17\\ 2x-5=-11\\ 2x=-11+5\\ x=-6:2\\ x=-3\)
\(\text{2/ 10 - 2(4 - 3x) = - 4}\\ 2\left(4-3x\right)=10-\left(-4\right)\\ 2\left(4-3x\right)=14\\ 4-3x=14:2\\ 4-3x=7\\ 3x=4-7\\ x=-3:3\\ x=-1\)
-45:5.(-3-2x)=3
-45 : 5 . ( -3 - 2x ) = 3
5 . ( -3 - 2x ) = -15
-3 - 2x = -3
2x = 0
x = 0 : 2
x = 0
<=> -9 . ( -3 -2x ) = 3
<=> 27 + 18x = 3
<=> 18x = 3 - 27
<=> 18x = -24
<=> x = -24 : 18
<=> x = -4/3
-45:5(-3-2x)=3
-45:5(-3-2x)=3
5(-3-2x)= -45:3
5(-3-2x)=-15
-3-2x= -15:5
-3-2x= -3
2x= -3-(-3)
2x= 0
x= 0:2
x= 0
Vậy x= 0
-45:5(-3-2x) = 3
5(-3-2x) = 3.(-45)
5(-3-2x) = -135
-3-2x = (-135) : 5
-3-2x = -27
2x = (-27) + (-3)
2x = -30
x = (-30) : 2
x = -15
- 45 : 5 ( - 3 - 2x ) = 3
- 45 : ( - 15 ) - 5 . 2x = 3
3 - 5 . 2x = 3
5 . 2x = 3 - 3
5 . 2x = 0
2x = 0 : 5
2x = 0
x = 0 : 2
x = 0
BÀI 4: TÌM X (ghi rõ cách tính và kết quả)
1) 3x – 15 = 45
2) 35 – 5x = 50
3) (2x – 5) + 17 = 6
4) 10 – 2(4 – 3x) = -4
5) - 12 + 3(-x + 7) = -18
6) 24 : (3x – 2) = -3
7) -45 : 5.(-3 – 2x) = 3
1) 3x = 45 + 15 = 60
x = 60 : 3 = 20
2) 5x = 50 - 35 = 15
x = 15 : 5 = 3
3) (2x - 5) + 17 = 6
2x - 5 = 6 - 17
2x - 5 = -11
2x = -11 + 5
2x = -6
x = -6 : 2 = -3
4) 10 - 2(4 -3x) = -4
2(4 - 3x) = -4 - 10 = -14
4 - 3x = -14 : 2 = -7
3x = -7 - 4 = -18
x = -18 : 3 = -6
BÀI 4: TÌM X (ghi rõ từng bước của phép tính)
1) 3x – 15 = 45
2) 35 – 5x = 50
3) (2x – 5) + 17 = 6
4) 10 – 2(4 – 3x) = -4
5) - 12 + 3(-x + 7) = -18
6) 24 : (3x – 2) = -3
7) -45 : 5.(-3 – 2x) = 3
\(\left\{{}\begin{matrix}\left\{{}\begin{matrix}3x-15=45\Leftrightarrow3x=60\Leftrightarrow x=20\\35-5x=50\Leftrightarrow5x=-15\Leftrightarrow x=-3\end{matrix}\right.\\\left\{{}\begin{matrix}\left(2x-5\right)+17=6\Leftrightarrow2x+5=-11\Leftrightarrow2x=-16\Leftrightarrow x=-8\\10-2\left(4-3x\right)=-4\Leftrightarrow8-6x=14\Leftrightarrow6x=-6\Leftrightarrow x=-1\end{matrix}\right.\\\left\{{}\begin{matrix}-12+3\left(-x+7\right)=-18\Leftrightarrow-3x+21=-6\Leftrightarrow-3x=-27\Leftrightarrow x=9\\24:\left(3x-2\right)=-3\Leftrightarrow3x-2=-8\Leftrightarrow3x=-6\Leftrightarrow x=-2\end{matrix}\right.\\-45:5\left(-3-2x\right)=3\Leftrightarrow-15-10x=-15\Leftrightarrow10x=0\Leftrightarrow x=0\end{matrix}\right.\)
BÀI 4: TÌM X (ghi rõ cách tính và kết quả)
1) 3x – 15 = 45
2) 35 – 5x = 50
3) (2x – 5) + 17 = 6
4) 10 – 2(4 – 3x) = -4
5) - 12 + 3(-x + 7) = -18
6) 24 : (3x – 2) = -3
7) -45 : 5.(-3 – 2x) = 3
A) 2x-4=2^5:2^3
B)60:2x+50=60
C)70-5.(2x-3)=45
D)(3x-6).3=3^4
a/ => 2x - 4 = 22 = 4
=> 2x = 8
=> x = 4
b/ => 60 : 2x = 10
=> 2x = 6
=> x = 3
c/ => 5(2x - 3) = 25
=> 2x - 3 = 5
=> 2x = 8
=> x = 4
d/ => 3x - 6 = 34 : 3 = 33 = 27
=> 3x = 33
=> x = 11
5(7+48:x)=45
5^2x-3-2*5^2=5^2*3
2+x:5=6
10+2x=4^5:4^3
\(5\left(7+48:x\right)=45\)
\(\Leftrightarrow\left(7+48x\right)=9\)
\(\Leftrightarrow4x=2\)
\(\Leftrightarrow x=2\)
________________
\(5^2x-3.2.5^2=5^2.3\)
\(\Leftrightarrow5x^2-3-2.5^2=75\)
\(\Leftrightarrow5x^2-3-50=75\)
\(\Leftrightarrow5x^2-3=125\)
\(\Leftrightarrow5x^2=128\)
\(\Leftrightarrow x^2=\frac{128}{5}\)
\(\Leftrightarrow\orbr{\begin{cases}x=\frac{128}{5}\\x=-\frac{128}{5}\end{cases}}\)
___________________
\(2+x:5=0\)
\(\Leftrightarrow x:5=-2\)
\(\Leftrightarrow x=-10\)
\(10+2x=16\)
\(\Leftrightarrow2x=6\)
\(\Leftrightarrow x=3\)