a) 15 – ( 4 – x) = 6 ; b) – 30 + ( 25 – x) = – 1 ;
c) x – ( 12 – 25) = -8 ; d) ( x – 29 ) – ( 17 – 38 ) = – 9
a) 15 – ( 4 – x) = 6 ; b) – 30 + ( 25 – x) = – 1 ; c) x – ( 12 – 25) = -8 ;
By Gianna
Đáp án:
Giải thích các bước giải:
a,15- (4-x)=6
—>15-4+x=6
–>11+x=6
—>x=-5
b,-30+(25-x)=-1
—>-30+25-x=-1
—->-5-x=-1
—>x=-4
c,x-(12-25)=-8
—>x+13=-8
—>x=-21
d,(x-29)-(17-38)=-9
—>x-29+21=-9
—->x=-1
a) 15 – ( 4 – x) = 6
4 – x = 15 – 6
4 – x = 9
x = 4 – 9
x = -5
vậy x=-5
b) – 30 + ( 25 – x) = – 1
25 – x = -1 -(-30)
25 – x = -1 +30
25 – x = 29
x = 25 – 29
x = -4
vậy x = – 4
c) x – ( 12 – 25) = -8
x – (-13) = -8
x =-8 + (-13)
x = -21
vậy x=-21
d)( x – 29 ) – ( 17 – 38 ) = – 9
( x – 29 ) – (-21) =-9
x – 29 =-9 + (-21)
x – 29 = -30
x = -30 + 29
x =-1
vậy x=-1