Đáp án:
10)
a)x=4
b)x=-34
c)x=-21
d)x=-10
e)x=6
f)x=66
11)
a)30
b)-123
c)32
d)13
Giải thích các bước giải:
10)
a)x-5=-1
<=>x=-1+5
<=>x=4
b)x+30=-4
<=>x=-4-30
<=>x=-34
c)x-(-24)=3
<=>x+24=3
<=>x=3-24
<=>x=-21
d)22-(-x)=12
<=>22+x=12
<=>x=12-22
<=>x=-10
e)(x+5)+(x-9)=x+2
<=>x+5+x-9=x+2
<=>x+x-x=2-5+9
<=>x=6
f)(27-x)+(15+x)=x-24
<=>27-x+15+x=x-24
<=>-x+x-x=-24-15-27
<=>-x=-66
<=>x=66
11)
a)-37+54+(-70)+(-163)+246
=-37+(-163)+54+246+(-70)
=-200+300-70
=30
b)-359+181+(-123)+350+(-172)
=-359+350+181-172-123
=-9+9-123
=-123
c)-69+53+46+(-94)+(-14)+78
=-69+53-94+78+46-14
=16-16+32
=32
d)13-12+11+10-9+8-7-6+5-4+3+2-1
=-12+2+11-1+10-6-4+13+3-9-7+8+5
=-10+10+10-10+16-16+13
=13
Học tốt!!
