Question

îmi rezolvați aceste exerciții?

Answer 1

Răspuns

1) (3+7a):8=10

(3+7a)=80

7a=77⇒a=11

2) (9a-120)x3-100=80

(9a-120)x3=180

(9a-120)=60

9a=180⇒a=20

3) 100:(10+10x(10-10:a)=10

10+10x(10-10:a)=10

10x(10-10:a)=0

10-10:a=0

10:a=10 a=1

Explicație pas cu pas:

Answer 2

h)

( 3 + 7 × a ) : 8 + 50 = 60

( 3 + 7 × a ) : 8 = 60 - 50

( 3 + 7 × a ) : 8 = 10

3 + 7 × a = 10 × 8

3 + 7 × a = 80

7 × a = 80 - 3

7 × a = 77

a = 77 : 7

a = 11

i)

240 : [ ( 9 × a - 120 ) × 3 - 100 ] = 3

[ ( 9 × a - 120 ) × 3 - 100 ] = 240 : 3

[ ( 9 × a - 120 ) × 3 - 100 ] = 80

[ ( 9 × a - 120 ) × 3 ] = 80 + 100

[ ( 9 × a - 120 ) × 3 ] = 180

9 × a - 120 = 180 : 3

9 × a - 120 = 60

9 × a = 60 + 120

9 × a = 180

a = 180 : 9

a = 20

j)

10 + 100 : [ 10 + 10 × ( 10 - 10 : a ) ] - 20 = 0

10 + 100 : [ 10 + 10 × ( 10 - 10 : a ) ] = 0 + 20

10 + 100 : [ 10 + 10 × ( 10 - 10 : a ) ] = 20

100 : [ 10 + 10 × ( 10 - 10 : a ) ] = 20 - 10

100 : [ 10 + 10 × ( 10 - 10 : a ) ] = 10

[ 10 + 10 × ( 10 - 10 : a ) ] = 100 : 10

[ 10 + 10 × ( 10 - 10 : a ) ] = 10

[ 10 × ( 10 - 10 : a ) ] = 10 - 10

[ 10 × ( 10 - 10 : a ) ] = 0

10 - 10 : a = 0 : 10

10 - 10 : a = 0

10 : a = 10 - 0

10 : a = 10

a = 10 : 10

a = 1