4A
a)Ta có: VT=-(59-3x)+39=-59+3x+39=3x-20=VP
b)Ta có: VT=-(a+b+c)+(b-c)-(a-c-1)=-a-b-c+b-c-a+c+1=-2a-c+1=VP
4B.
a) Ta có: VT=-(19-2x)+39=-19+2x+39=2x+20=VP
b)Ta có: VT=--(a+b+c)+(b-c)-(a-c+1)=-a-b-c+b-c-a+c-1=-2a-c-1=VP
5A
a)35-x=16-(-2)
35-x=18
x=35-18
x=17
Vậy x=17
b)x-2=-7-9
x-2=-16
x=-16+2
x=-14
Vậy x=-14
5B
a)15-x=11-(-2)
15-x=13
x=15-13
x=2
Vậy x=2
b)x-1=-2-3
x-1=-5
x=-5+1
x=-4
Vậy x=-4
Chúc bn hc tốt, cho mk 5 sao, hay nhất và cảm ơn nha^^
#English and Maths
#Alex_Armanto_Siro :3
