a, \(x+29=\left|-43\right|+\left(-43\right)\)

\(\Rightarrow x+29=0\)

\(\Rightarrow x=-29\)

c, \(\left(-1\right)+3+\left(-5\right)+7+...+x=600\)

\(\Rightarrow2+2+....+x=600\)

Để kết quả bằng 600 thì phải có 3000 cặp số tương ứng có 600 số trong dãy số và x là số 600 cuối cùng \(\Rightarrow x=1199\)

g, \(2+\left(-4\right)+6+\left(-8\right)+...+\left(-x\right)=-2000\)

\(\Leftrightarrow\left(-2\right)+\left(-2\right)+...+\left(2\right)=-2000\)

\(\Leftrightarrow\left(-2\right).\left(\dfrac{x-2}{2}+1\right)=-200\)

\(\Leftrightarrow\dfrac{x-2}{2}+1=400\)

\(\Leftrightarrow x=800\)

-Chúc bạn học tốt-

Giải:

a) \(x+29=\left|-43\right|+\left(-43\right)\) 

    \(x+29=43+\left(-43\right)\) 

    \(x+29=0\) 

            \(x=0-29\) 

            \(x=-29\) 

b) \(\left|x\right|-\left(-2\right)=\left(-1\right)\) 

                \(\left|x\right|=\left(-1\right)+\left(-2\right)\) 

                \(\left|x\right|=-3\) 

Vì giá trị tuyệt đối của một số ko bao giờ đc kết quả là số âm nên x ∈ ∅.

c) \(\left(-1\right)+3+\left(-5\right)+7+...+x=600\) 

\(\Rightarrow2+2+...+2=600\) 

\(\Rightarrow2.\left(\dfrac{x-1}{2}+1\right):2=600\) 

\(\Rightarrow\dfrac{x-1}{2}+1=600\) 

\(\Rightarrow\dfrac{x-1}{2}=599\) 

\(\Rightarrow x-1=1198\) 

\(\Rightarrow x=1199\) 

Chúc bạn học tốt!

b; |\(x\)| - (-2) = (-1)

    |\(x\)| + 2 = -1

    |\(x\)| = - 1 - 2

    |\(x\)| = -3 (vô lý vì |\(x\)| ≥ 0 ∀\(x\)

Vậy \(x\in\varnothing\)

1. \(x-8+32=68\)

\(x-8=68-32\)

\(x-8=36\)

\(x=36+8\)

\(x=44\)

_____

2. \(x+8+32=68\)

\(x+8=68-32\)

\(x+8=36\)

\(x=36-8\)

\(x=28\)

_____

3. \(98-x+34=43\)

\(98-x=43-34\)

\(98-x=9\)

\(x=98-9\)

\(x=89\)

_____

4. \(98+x-34=43\)

\(98+x=43+34\)

\(98+x=77\)

\(x=77-98\)

\(x=-21\)

_____

5. \(x:5:4=800\)

\(x:5=800.4\)

\(x:5=3200\)

\(x=3200.5\)

\(x=16000\)

_____

6. \(18+x=384:8\)

\(18+x=48\)

\(x=48-18\)

\(x=30\)

_____

7. \(\left(84,6-2\times x\right):3,02=5,1\)

\(84,6-2.x=5,1.3,02\)

\(84,6-2.x=15,402\)

\(2.x=84,6-15,402\)

\(2.x=69,198\)

\(x=69,198:2\)

\(x=34,599\)

_____

8. \(x\times5=120:6\)

\(x.5=20\)

\(x=20:5\)

\(x=4\)

_____

9. \(\left(15\times24-x\right):0,25=100:0,25\)

\(\left(15.24-x\right):0,25=400\)

\(15.24-x=400.0,25\)

\(15.24-x=100\)

\(360-x=100\)

\(x=360-100\)

\(x=260\)

1,x-8+32=68

=>x-8=68-32=36

=>x=36+8=42

2,x+8+32=68

=>x+8=68-32=36

=>x=36-8=28

3,98-x+34=43

=>98-x=43-34=9

=>x=98-9=89

4,98+x-34=43

=>98+x=43+34=77

=>x=77-98=-21

5,x:5:4=800

=>x:20=800

=>x=800x20=16000

6,18+x=384:8=48

=>x=48-18=30

7,(84,6-2x):3,02=5,1

=>84,6-2x=5,1x3,02=15,402

=>2x=84,6-15,402=69,198

=>x=69,198:2=34,599

8,5x=120:6=20

=>x=20:5=4

9,(15x24-x):0,25=100:0,25=400

=>360-x=400x0,25=100

=>x=360-100=260.

1. \(...\Rightarrow x+24=68\Rightarrow x=68-24=44\)

2. \(...\Rightarrow x+40=68\Rightarrow x=68-40=28\)

3. \(...\Rightarrow3^{2\left(8+x\right)}=9=3^2\Rightarrow2\left(8+x\right)=2\Rightarrow8+x=1\Rightarrow x=-7\)

4. \(...\Rightarrow3^{2\left(8+x\right)}=77\) (bạn xem lại đề)

5. \(...\Rightarrow x:5=800.4\Rightarrow x:5=3200\Rightarrow x=3200.5=16000\)

6. \(...\Rightarrow18+x=48\Rightarrow x=48-18=30\)

7. \(...\Rightarrow84,6-2x=5,1.3,02=15,402\Rightarrow2x=84,6-15,402\Rightarrow2x=69,198\Rightarrow x=34,599\)

8. \(...\Rightarrow5.x=20\Rightarrow x=20:5=4\)

9. \(\left(360-x\right):0,25=400\Rightarrow360-x=400.0,25=100\Rightarrow x=400-100=300\)

\(\dfrac{5}{2x1}+\dfrac{4}{1x11}+\dfrac{3}{11x2}+\dfrac{1}{2x15}+\dfrac{13}{15x4}+\dfrac{15}{4x13}\)

=7x(\(\dfrac{5}{2x7}+\dfrac{4}{7x11}+\dfrac{3}{11x14}+\dfrac{1}{14x15}+\dfrac{13}{15x28}+\dfrac{15}{28x43}\))

=7x\(\dfrac{1}{2}-\dfrac{1}{7}+\dfrac{1}{7}-\dfrac{1}{11}+\dfrac{1}{11}-\dfrac{1}{14}+\dfrac{1}{14}-\dfrac{1}{15}+\dfrac{1}{15}-\dfrac{1}{28}+\dfrac{1}{28}-\dfrac{1}{43}\)=7x(\(\dfrac{1}{2}-\dfrac{1}{43}\))

=7x\(\dfrac{41}{86}\)

=\(\dfrac{287}{86}\)

5/2x1+4/1x11+3/11x2+1/2x15+13/15x4+15/4x43=7x(5/2x7+4/7x11+3/11x14+1/14x15+13/15x28+15/28x43)=7x(1/2-1/7+1/7-1/11+1/11-1/14+1/14+1/15+1/15-1/28+1/28-1/43)=7x(1/2-1/43)=7x41/86=287/86

a)2500

b)2772

c)1974

d)347

e)1874

k mk nha

a,25x100=2500

b,

(dấu chấm là dấu nhân nha e)

 *\(\dfrac{1}{2}\). \(\dfrac{1}{4}\)+\(\dfrac{3}{4}\)

= \(\dfrac{1}{8}\)+\(\dfrac{3}{4}\)

= \(\dfrac{1}{8}\)+\(\dfrac{6}{8}\)= \(\dfrac{7}{8}\)

 *\(\dfrac{3}{4}\).\(\dfrac{5}{6}\).\(\dfrac{8}{15}\)

= \(\left(\dfrac{3}{4}.\dfrac{8}{15}\right)\).\(\dfrac{5}{6}\)

= \(\dfrac{2}{5}\).\(\dfrac{5}{6}\)

= \(\dfrac{1}{3}\)

 *\(\dfrac{12}{19}\): \(\dfrac{17}{38}\).\(\dfrac{16}{9}\)

= \(\dfrac{12}{19}\). \(\dfrac{38}{17}\).\(\dfrac{16}{9}\)= 2,5

1/8+3/4=7/8

5/8x8/15=1/3

24/17x16/9=128/51

1/2x1/4+3/4=7/8

3/4x5/6x8/15=1/3

12/19:17/38x16/9=128/51

1/8+3/4=7/8

5/8x8/15=1/3

24/17x16/9=128/51