tìm x
91-[ 27+x] = 38
39+[x-17] = 72
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
\(\left(x-27\right)\cdot91-72=215\cdot91-72\)
\(\left(x-27\right)\cdot91=215\cdot91-72+72\)
\(\left(x-27\right)\cdot91=215\cdot91\)
\(\left(x-27\right)=215\cdot91:91\)
\(x-27=215\)
\(x=242\)
\(\left(x-27\right).91-72=215.91-72\)
Do 2 đẳng thức trên bằng nhau nên rút gọn 2 vế với - 7 ta đc
\(\Rightarrow\left(x-27\right).91=215.91\)
\(\Rightarrow\left(x-27\right)=215\)
\(\Rightarrow x=215+27=242\)
`@` `\text {Ans}`
`\downarrow`
`2023 \times 14 + 2023 \times 83+97`
`= 2023 \times (14+83) + 97`
`= 2023 \times 97 + 97`
`= 196231 +97`
`= 196328`
`78 \times 31+78 \times 24+78 \times 17+78 \times 22 \times 72`
`= 78 \times (31+24+17+22 \times 72)`
`= 78 \times (31+24+17+1584)`
`= 78 \times 1656`
`= 129168`
`371 \times 69+371 \times 14+629 \times 83`
`= 371 \times (69+14) + 629 \times 83`
`= 371 \times 83 + 629 \times 83`
`= 83 \times (371+629)`
`= 83 \times 1000`
`= 83000`
`91 \times 51+49 \times 163-49 \times 72`
`= 91 \times 51 + 49 \times (163-72)`
`= 91 \times 51+49 \times 91`
`= 91 \times (51+49)`
`= 91 \times 100`
`= 9100`
`3 \times 12 \times 17 + 4 \times 9 \times 81 + 2 \times 6 \times 6`
`= 9 \times 4 \times 17 + 4 \times 9 \times 81 + 4 \times 9 \times 2`
`= 9 \times 4 \times (17+81+2)`
`= 36 \times 100`
`= 3600`
`42 \times 17 + 58 \times 83 \times 42 \times 83 + 42 \times 83 + 17`
`= 17 \times (42+58) + 42 \times 83 \times (58 \times 83 +1)`
`= 17 \times 100 + 3486 \times 4815`
`= 1700 + 16785090`
`= 16786790`
n: (-8)*x+17=-23
=>\(x\cdot\left(-8\right)=-23-17=-40\)
=>\(x\cdot8=40\)
=>\(x=\dfrac{40}{8}=5\)
o: \(\left(-15\right)\cdot x=10\left(-4\right)-5\)
=>\(x\cdot\left(-15\right)=-40-5=-45\)
=>\(x\cdot15=45\)
=>\(x=\dfrac{45}{15}=3\)
p: \(\left(-3\right)\cdot x-4=2\cdot\left(-7\right)+4\)
=>\(\left(-3\right)\cdot x-4=-14+4=-10\)
=>\(x\left(-3\right)=-10+4=-6\)
=>\(3x=6\)
=>\(x=\dfrac{6}{3}=2\)
q: x+x+x+91=-2
=>\(3x+91=-2\)
=>\(3x=-2-91=-93\)
=>\(x=-\dfrac{93}{3}=-31\)
r: \(-152-\left(3x+1\right)=\left(-2\right)\cdot\left(-27\right)\)
=>\(-152-3x-1=54\)
=>\(-153-3x=54\)
=>\(3x=-153-54=-207\)
=>\(x=-\dfrac{207}{3}=-69\)
17 - 2x = -15
2x = 17 - (-15)
2x = 32
x = 32 : 2
x = 16
--------
54 : (x + 2) = -6
x + 2 = 54 : (-6)
x + 2 = -9
x = -9 - 2
x = -11
--------
12.(3 - x) = 72
3 - x = 72 : 12
3 - x = 6
x = 3 - 6
x = -3
-------
-3(x + 5) + 18 = -27
-3(x + 5) = -27 - 18
-3(x + 5) = -45
x + 5 = -45 : (-3)
x + 5 = 15
x = 15 - 5
x = 10
-------
(x + 5)² = 9
x + 5 = 3 hoặc x + 5 = -3
*) x + 5 = 3
x = 3 - 5
x = -2
*) x + 5 = -3
x = -3 - 5
x = -8
Vậy x = -8; x = -2
--------
(3 - x)³ = 27
(3 - x)³ = 3³
3 - x = 3
x = 3 - 3
x = 0
Ta có : 91-(27+x)=38
<=>91-27-x=38
<=>91-27-38=x
<=>x=26
39+(x-17)=72
<=>39+x-17=72
<=>x=72+17-39
<=>x=50
Tk mình nha!
\(91-\left(27+x\right)=28\)
\(27+x=91-28\)
\(27+x=63\)
\(x=63-27\)
\(x=36\)
\(39+\left(x-17\right)=72\)
\(x-17=72-39\)
\(x-17=33\)
\(x=33+17\)
\(x=50\)
hok tốt