Question

PLS dau coroană ex 1

Answer 1

1. x - (x:7 + 11) = 55

x - x : 7 - 11 = 55

x - x : 7 = 66

7x - x = 462

6x = 462

x = 77

2. a + ( a + a : a) = 17

a + a + 1 = 17

2a = 16

a = 8

3.  a - (13  + a : 3) = 15

a - 13 - a : 3 = 15

a - a : 3 = 28

3a - a = 84

2a = 84

a = 42

4. 62 - [ a + ( a: 3 + 4 ) + a ]  =23

62 - a - a :3 - 4 - a = 23

a - a : 3 - 4 - a = 39

a : 3 = 43

a = 43 x 3

a = 129

Answer 2

1.

x-(x:7+11)=55

x-(⅐x+11)=55

x-⅐x-11=55

⁶/₇x-11=55

6x-77=385

6x=385+77

6x=462

x=77

2.

a+(a+a:a)=17

a+(a+a:a)=17, a≠0

a+(a+1)=17

a+a+1=17

2a+1=17

2a=17-1

2a=16

a=8, a≠0

a=8

3.

a-(13+a:3)=15

a-(13+⅓a)=15

a-13-⅓a=15

⅔a-13=15

2a-39=45

2a=45+39

2a=84

a=42

4.

62-[a+(a:3+4)+a]=23

62-[a+(⅓a+4)+a]=23

62-(a+(⅓a+4+a)=23

62-(⁷/₃a+4)=23

62-⁷/₃a-4=23

58-⁷/₃a=23

174-7a=69

-7a=69-174

-7a=-105

a=15