a) 2x - 5 = 9
2x = 14
x = 7
b) 5x - 138 = 23 . 32
5x - 138 = 72
5x = 210
x = 42
A) 2x - 5 = 9
2x = 9 + 5
2x = 14
x = 14 : 2
x = 7
B) 5x - 138 = \(2^3.3^2\)
5x - 138 = 8 . 9
5x - 138 = 72
5x = 72 + 138
5x = 210
5x= 210
\(A:2x-5=9\)
\(\Rightarrow2x=9+5=14\)
\(\Rightarrow x=14:2=7\)
A: 2x-5=9 B: 5x-138=23.32
2x=9+5 5x-138=8.9
2x=14 5x-138=72
x=14/2 5x =72+138
x=7 5x =200
Vậy x=7 x =200:5
x =40
Vậy x=40
Mình mới vào dùng mong bạn thông cảm!
\(B:5x-138=2^3.3^2\)
\(\Rightarrow5x-138=8.9=72\)
\(\Rightarrow5x=72+138=210\)
\(\Rightarrow x=210:5=42\)
a) 2x - 5 = 9
2x = 9 + 5
2x = 14
x = 14 : 2
x = 7
Vay x = 7
b) 5x - 138 =23. 32
5x - 138 = 8 . 9
5x - 138 = 72
5x = 72 + 138
5x = 210
x = 210 : 5
x = 42
Vay x = 42
CHUC BAN HOC TOT !
a, 2x - 5 = 9
2x = 14
=> x = 7
b, 5x - 138 = 23 .32
5x - 138 = 8 . 9
5x - 138 = 72
5x = 210
=> x = 42
Ta có : 2x - 5 = 9
=> 2x = 9 + 5 = 14
=> x = 14 : 2 = 7
HK tốt ..........
Ta có : 2x - 5 = 9
=> 2x = 9 + 5 = 14
=> x = 14 :2 = 7
HK TỐT .............
