a) 7 - x =8-(-7) b) x-8 = (-3)-8
7 - x = 15 x-8 = -11
x = 7-15 x = -11+8
x = -8 x = -3
a,7-x=15
x=7-15=-8
b,x-8=-11
x=-11+8=-3
tick minh
7-x=15
x=7-15
x--8
b,x-8=-11
x=-11+8
x=-3
tich minh
a,7-x=8-(-7)
7-x=15
x=7-15
x=-8
b,x-8=(-3)-8
x-8=-11
x=-11+8
x=-2
tick cho mk nha