Question

cu explicatie va rog frumos
Aflati termenul necunoscut din egalitatea :

40 - { [ ( 2 x a – 8 ) x 2 – 12 ] : 4 – 1 } x 10 = 30

Answer 1

Răspuns:

Explicație pas cu pas:

40 - { [ ( 2 x a – 8 ) x 2 – 12 ] : 4 – 1 } x 10 = 30

{ [ ( 2 x a – 8 ) x 2 – 12 ] : 4 – 1 } x 10 = 40 - 30

{ [ ( 2 x a – 8 ) x 2 – 12 ] : 4 – 1 } x 10 = 10

[ ( 2 x a – 8 ) x 2 – 12 ] : 4 – 1 = 10 : 10

[ ( 2 x a – 8 ) x 2 – 12 ] : 4 – 1 = 1

[ ( 2 x a – 8 ) x 2 – 12 ] : 4 = 1 + 1

[ ( 2 x a – 8 ) x 2 – 12 ] : 4 = 2

( 2 x a – 8 ) x 2 – 12 = 2 × 4

( 2 x a – 8 ) x 2 – 12 = 8

( 2 x a – 8 ) x 2 = 8 + 12

( 2 x a – 8 ) x 2 = 20

2 x a – 8 = 20 : 2

2 x a – 8 = 10

2 x a = 10 + 8

2 x a = 18

a = 18 : 2

a = 9 → numarul, aflat prin metoda mersului invers