a) ( x - 15 ) - 75 = 0
<=> x - 15 = 75
<=> x = 90
b) 575 - ( 6x + 70 ) = 445
<=> 6x + 70 = 130
<=> 6x = 60
<=> x = 10
c) 315 + ( 125 - x ) = 435
<=> 125 - x = 120
<=> x = 5
a, ( x - 15 ) - 75 = 0
x - 15 = 0 + 75
x - 15 = 75
x = 75 + 15
x = 90
b, 575 - ( 6x + 70 ) = 445
6x + 70 = 575 - 445
6x + 70 = 130
6x = 130 - 70
6x = 60
x = 60 : 6
x = 10
c, 315 + ( 125 - x ) = 435
125 - x = 435 - 315
125 - x = 120
x = 125 - 120
x = 5
Học tốt
(x-15)=0+75
(x-15)=75
x=75+15
x=90
vậy x=90
(6x+70)=575-445
(6x+70)=130
6x=130-70
6x=60
x=60:6
x=10
vậy x=10
(125-x)=435-315
(125-x)=120
x=125-120
x=5
vậy x=5
a. ( x- 15 ) - 75 = 0
x = 15+75
x = 90
b. 575 - ( 6x + 70 ) = 445
505 - 6x = 445
-6x = 445 - 505
- 6x = - 60
x = 10
c. 315 + (125 - x ) = 435
125 - x = 435 - 315
125 - x = 120
-x = 120 - 125
- x = -5
x = 5
Chúc cậu học tốt! ( > v < )
a, \(\left(x-15\right)-75=0\Leftrightarrow x-15-75=0\)
\(\Leftrightarrow x-90=0\Leftrightarrow x=90\)
b, \(575-\left(6x+70\right)=445\Leftrightarrow575-6x-70=445\)
\(\Leftrightarrow505-6x=445\Leftrightarrow6x=60\Leftrightarrow x=10\)
c, \(315+\left(125-x\right)=435\Leftrightarrow315+125-x=435\)
\(\Leftrightarrow440-x=435\Leftrightarrow x=5\)
