a) 13 - ( -20 ) + x = 80 : 2
33 + x = 40
x = 40 - 33
x = 7
b) -13 + ( -20 ) + x = ( - 490 ) + 27
- 33 + x = -463
x = -463 - ( -33 )
x = -430
a) 13-(-20)+x=80:2
13+20+x=40
33+x=40
x=40-33
x=7
b) -13+(-20)+x=(-490)+27
-33+x=-463
x=-463+33
x=-430
Tìm x , biết :
a ) 13 - ( - 20 ) + x = 80 : 2
13 + 20 + x = 80 : 2
33 + x = 40
x = 40 - 33
x = 7
Vậy x = 7
b ) - 13 + ( - 20 ) + x = ( - 490 ) + 27
- 33 + x = - 463
x = - 463 - ( - 33 )
x = - 430
Vậy x = - 430