Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a)-Ix-3I+16=4
-Ix-3I=4-16
-Ix-3I=-12
-IxI=-12+3
-IxI=-9
x=-9
b)3-(17-x)=289-(36+289)
3-(17-x)=289-325
3-(17-x)=-36
(17-x)=3-(-36)
(17-x)=39
x=17-39
x=-22
c)25-(x+5)=415-(15-415)
25-(x+5)=415-(-400)
25-(x+5)=815
(x+5)=25-815
(x+5)=-790
x=(-790)-5
x=-795
d)34+(21-x)=(3747-30)-3746
34+(21-x)=3717-3746
34+(21-x)=-29
31+x=21-(-29)
31+x=50
x=50-31
x=19
k) 3 - ( 17 - x ) = 289 - ( 36 + 289 )
3 - 17 + x = 289 - 36 - 289
x = 289 - 36 - 289 - 3 + 17
x = -22
n) 25 - ( x + 15 ) = ( -415 ) - ( 15 - 415 )
25 - x - 15 = -415 - 15 + 415
25 - x - 15 = -15
25 - 15 + 15 = -x
-x = 25
=> x = -25
m) 34 + ( 21 - x ) = ( 3747 - 30 ) - 3747
34 + 21 - x = 3747 - 30 - 3747
34 + 21 - x = -30
34 + 21 + 30 = -x
-x = 85
=> x = -85
r) Hình như thiếu đề thì phải
HỌC TỐT !
trả lời :
mấy câu kia bạn tham khảo bạn I love You nha
còn câu r) thiếu đề x+2+15:|-3|=? ( chưa có kết quả)
học tốt
1,
a) |x| + |y + 1| =0
Ta có: |x| \(\ge\) 0 (Với x \(\in\) Z)
|y + 1| \(\ge\) 0 (Với y\(\in\) Z)
\(\Rightarrow\) |x| + |y + 1| \(\ge\) 0
Dấu "=" xảy ra (=):
\(\left\{\begin{matrix}\left|x\right|=0\\\left|y+1\right|=0\end{matrix}\right.\Rightarrow\left\{\begin{matrix}x=0\\y+1=0\end{matrix}\right.\Rightarrow}\left\{\begin{matrix}x=0\\y=0-1\end{matrix}\right.\Rightarrow}\left\{\begin{matrix}x=0\\y=-1\end{matrix}\right.\)
Vậy x = 0; y = -1
b) (2 - x)4 = 81
\(\Rightarrow\) (2 - x)4 = 34 = (-3)4
\(\Rightarrow\) \(\left[\begin{matrix}2-x=3\\2-x=-3\end{matrix}\right.\Rightarrow\left[\begin{matrix}x=2-3\\x=2-\left(-3\right)\end{matrix}\right.\Rightarrow\left[\begin{matrix}x=-1\\x=5\end{matrix}\right.\)
Vậy: x \(\in\) {-1; 5}
c) |x - 1| + (-3) = 17
\(\Rightarrow\) |x - 1| = 17 - (-3)
\(\Rightarrow\) |x - 1| = 20
\(\Rightarrow\left[\begin{matrix}x-1=-20\\x-1=20\end{matrix}\right.\Rightarrow\left[\begin{matrix}x=-20+1\\x=20+1\end{matrix}\right.\Rightarrow\left[\begin{matrix}x=-19\\x=21\end{matrix}\right.\)
Vậy: x \(\in\) {-19; 21}
d) 3 - (17 - x) = 289 - (36 + 289)
\(\Rightarrow\) 3 - (17 - x) = 289 - 36 - 289
\(\Rightarrow\) 3 - (17 - x) = 289 - 289 - 36\(\Rightarrow\) 3 - (17 - x) = 0 - 36
\(\Rightarrow\) 3 - (17 - x) = -36 \(\Rightarrow\) 17 - x = 3 - (-36) \(\Rightarrow\) 17 - x = 39 \(\Rightarrow\) x = 17 - 39 \(\Rightarrow\) x = -22 Vậy: x = -22 e) 25 - (x + 5) = -415 - (15 - 415) \(\Rightarrow\) 25 - (x + 5) = -415 - 15 + 415 \(\Rightarrow\) 25 - (x + 5) = (-415 + 415) - 15 \(\Rightarrow\) 25 - (x + 5) = 0 - 15 \(\Rightarrow\) 25 - (x + 5) = -15 \(\Rightarrow\) x + 5 = 25 - (-15) \(\Rightarrow\) x + 5 = 40 \(\Rightarrow\) x = 40 -5 \(\Rightarrow\) x = 35 Vậy: x = 35 f) 34 + (21 - x) = (3747 - 30) - 3746 \(\Rightarrow\) 34 + (21 - x) = 3747 - 30 - 3746 \(\Rightarrow\) 34 + (21 - x) = 3747 - 3746 - 30 \(\Rightarrow\) 34 + (21 - x) = 1 - 30 \(\Rightarrow\) 34 + (21 - x) = -29 \(\Rightarrow\) 21 - x = -29 - 34 \(\Rightarrow\) 21 - x = -63 \(\Rightarrow\) x = 21 - (-63) \(\Rightarrow\) x = 84 Vậy: x = 84
3-(17-x)=289-(36+289)
<=> 3-17+x=289-36-289
<=> -14+x=-36 => x=-22
25-(x+5)=-45-(15-45)
<=> 25-x-5=-45-15+45
<=> 20-x=-15=> x=35
34-(21-x)=(3747-30)-3747
<=> 334-21+x=3747-30-3747
<=> 313+x=-30=> x=-343
3 - ( 17 - x ) = 289 - ( 36 + 289 )
3 - 17 + x = 289 - 36 - 289
- 14 + x = - 36
x = ( - 36 ) - ( - 14 )
x= - 22
25 - ( x + 5 ) = - 45 - ( 15 - 45)
25 - x - 5 = - 45 - 15 + 45
20 - x = - 15
x = 20 - ( - 15 )
x = 35
34 - ( 21 - x ) = ( 3747 - 30 ) - 3747
34 - 21 + x = 3747 - 30 - 3747
13 + x = - 30
x = ( - 30 ) - 13
x = - 46
a)3-[17-x]=289-325
[17-x]=3-(289-325)
[17-x]=3-(-36)
[17-x]=39
x=17-39
x=-22
b)25-[x+5]=-415-[15-415]
25-[x+5]=-415+400
25-[x+5]=-15
[x+5]=25+15
[x+5]=40
x=40-5
x=35
a) 3 - (17 - x) = 289 - (36 + 289)
3 - (17 - x) = 289 - 325
3 - (17 - x) = -36
17 - x = -36 - 3
17 - x = -39
x = -39 + 17
x = -22
b) 25 - (x + 5) = -415 - (15 - 415)
25 - (x + 5) = -415 - 400
25 - (x + 5) = -15
- (x + 5) = -15 - 25
- (x + 5) = -40
x + 5 = 40
x = 40 - 5
x = 35
c) 34 + (21 - x) = (3747 - 30) - 3746
34 + 21 - x = (3747 - 30) - 3746
55 - x = -29
x = 55 - (-29)
x = 84