a)15.x+15.2,7=105
15.(x+2,7)=105
x+2,7=7
x=7-2,7
x=4,3
Vậy x=4,3
b)x:7=920699:70
x:7=920699:10:7
x:7=92069,9:7
x=92069,9
Vậy x=92069,9
c)5.x-1952=2500-1947
5.x-1952=553
5.x=2505
x=501
Vậy x=501
d)x.2016-x=2016.2017+2016
x.(2016-1)=2016.(2017+1)
x.2015=2016.2018
x=\(\frac{2016.2018}{2015}\)
Vậy x\(\frac{2016.2018}{2015}\)
15.x+15.2,7=105
<=> 15.( x + 2,7 ) = 105
=> x + 2,7 = 7
=> x = 7 - 2,7
=> x = 4,3
x:7=920699:70
<=> x . 70 = 920699 . 7
=> x . 70 = 6444893
=> x = 6444893 : 70
=> x = 92069,9
5.x-1952=2500-1947
=> 5x - 1952 = 553
=> 5x = 553 + 1952
=> 5x = 2505
=> x = 2505 : 5
=> x = 501
x.2016-x=2016.2017+2016
=> x ( 2016 - 1 ) = 2016 ( 2017 + 1)
=> x . 2015 = 2016 . 2018
=> x : 2018 = 2016 : 2015
=> x : 2018 = \(\frac{2016}{2015}\)
=> x = \(\frac{2016}{2015}.2018\approx2019\)
