`7 xx x + 5 xx x = 175 + 125`

`( 7 + 5 ) xx x = 300`

`12 xx x = 300`

`x = 300 : 12`

`x = 25`

a) 7 x X +5 x X = 175 + 125.

7 + 5 x X = 300.

12 x X = 300.

x=300 : 12.

x=25.

Vậy X = 25.

Tick nha cảm ơn bạn.

a) \(\left[\left(x+32\right)-17\right].2=42\)

\(\left[\left(x+32\right)-17\right]=42:2\)

\(\left[\left(x+32\right)-17\right]=21\)

\(\left(x+32\right)=21+17\)

\(\left(x+32\right)=38\)

\(x=38-32\)

\(x=6\)

b) \(125+\left(145-x\right)=175\)

\(\left(145-x\right)=175-125\)

\(\left(145-x\right)=50\)

\(x=145-50\)

\(x=95\)

145x=175+125

145x=300

=>x=\(\frac{60}{29}\)

Lời giải:
1. Bạn coi lại đề

2. $=234\times (1257-257)=234\times 1000=234000$

3. $=175\times (1274-273-1)=175\times 1000=175000$

4. $=(4\times 25)\times (125\times 8)=100\times 1000=100000$

1. ...............................

2. $=234\times (1257-257)=234\times 1000=234000$

3. $=175\times (1274-273-1)=175\times 1000=175000$

4. $=(4\times 25)\times (125\times 8)=100\times 1000=100000$

a) (x - 25) - 130 = 150

=> x - 25            = 150 + 130

=> x - 25            = 280

=> x                   = 280 + 25

=> x                   = 305

c) 435 + 5.x = 135

=>          5.x = 135 - 435

=>          5.x = - 300

=>             x = -300 : 5

=>             x = - 60

\(\left(x-25\right)-130=150\)

\(\left(x-25\right)=150+130\)

\(\left(x-25\right)=280\)

\(x=280+25\)

\(x=305\)

a. (x - 25) - 130 = 150

               x - 25  = 280

               x         = 305

b. 125 + (145 - x) = 175

                145 - x  = 50

                          x  = 95

c. 435 + 5x = 135

              5x = -300

                x = -60

=>2x=5,8

hay x=2,9

x=2,9

2 câu đấy à?

\(125+173+175+27=\left(125+175\right)+\left(173+27\right)=300+200=500\)

\(125\times75+125\times25=125\times\left(75+25\right)=125\times100=12500\)