👤

4 x [(4 x m-72): 4 + 20] = 20


Răspuns :

Răspunde

4-[(4x-72):4+20]-64=20 4.[(4x-72):4+20]=20+64= 84 (4x-72):4+20= 84:4= 21 (4x-72):4=21-20-1 4x-72-4 4x=76 x= 76:4 x

Răspuns:

[tex]\boldsymbol{ \red{3}}[/tex]

Explicație pas cu pas:

4 × [(4 × m - 72) : 4 + 20] = 20

4 × (4 × m - 72) : 4 + 4 × 20 = 20

4 : 4 × (4 × m - 72) + 80 = 20

1 × (4 × m - 72) + 80 = 20

4 × m - 72 + 80 = 20

4 × m + 8 = 20

4 × m = 20 - 8

4 × m = 12

m = 12 : 4

m = 3

Metoda mersului invers:

(4 × m - 72) : 4 + 20 = 20 : 4

(4 × m - 72) : 4 + 20 = 5

(4 × m - 72) : 4 = 5 - 20

(4 × m - 72) : 4 = -15

4 × m - 72 = -15 × 4

4 × m - 72 = -60

4 × m = -60 + 72

4 × m = 12

m = 12 : 4

m = 3