13.(7x—49)—169=135:134
13.(7x—49)—169=13
13.(7x—49)=13+169
13.(7x—49)=182
7x—49=182:13
7x—49=14
7x=14+49
7x=63
x=63:7
x=9
13 . (7x - 49) - 169 = 135 : 134
13 . (7x - 49) - 169 = 13
(7x - 49) - 169 = 13:13
(7x - 49) - 169 = 1
7x - 49 = 1 + 169
7x - 49 = 170
7x = 170 - 49
7x = 121
x = 121 : 7
x = ?
\(13.\left(7x-49\right)-169=13^5:13^4\)
\(\Leftrightarrow13.\left(7x-49\right)-169=13^{5-4}\)
\(\Leftrightarrow13.\left(7x-49\right)-169=13\)
\(\Leftrightarrow13.\left(7x-49\right)=13+169\)
\(\Leftrightarrow13.\left(7x-49\right)=182\)
\(\Leftrightarrow7x-49=13:182\)
\(\Leftrightarrow7x-49=\frac{1}{14}\)
\(\Leftrightarrow7x=\frac{1}{14}+49\)
\(\Leftrightarrow7x=\frac{687}{14}\)
\(\Leftrightarrow x=\frac{687}{14}:7\)
\(\Leftrightarrow x=\frac{687}{98}\)
Học tốt #
13 . (7x - 49) - 169 = 135 : 134
13 . (7x - 49) - 169 = 13
(7x - 49) - 169 = 13 : 13
(7x - 49) - 169 = 1
7x - 49 = 1 + 169
7x - 49 = 170
7x = 170 + 49
7x = 219
x = 219 : 7
x = 219 / 7
13.(7x-49)-169=13^5:13^4
13.(7x-49)-169=13^1
13.(7x-49)-169=13
13.(7x-49)=13+169
13.(7x-49)=182
7x-49=182:13
7x-49=14
7x=14+49
7x=63
x=63:7
x=9
Vậy x=9