Question

Tìm x

71 - 2(15+ x ) =21

Answer 1

71-2(15+x) = 21

2(15+x) = 71-21

2(15+x) = 50

15+x = 50:2

15+x = 25

x = 25-15

x = 10

Answer 2

71 - 2 . (15+ x ) =21

=> 2 . ( 15 + x ) = 71 - 21

=> 2 . ( 15 + x ) = 50

=> 15 + x = 50 : 2

=> 15 + x = 25

=> x = 25 - 15

=> x = 10

Vậy x = 10

Answer 3

71-2.(15+x)=21

⇔2.(15+x)=71-21

⇔2.(15+x)=50

⇔15+x=50:2

⇔15+x=25

⇔x=25-15

⇒x=10

Answer 4

71-2(15+x)=21

2.(15+x)=71-21

2.(15+x)=50

15+x=50:2

15+x=25

x=25-15

x=10