Question

hey,vă rog ajutați-mă la acest video​

Answer 1

Răspuns:

A) a=3

B)a=7

C)b+c=11

Explicație pas cu pas:

A)2ab+2ac+4a=72

B+c=10

2A(b+c+2)=72

2a x(10+2)=72

2a x12=72

2a=72:12

2a=6

A=6:2

A=3

B)a(5b+5c+3)=441

A[5x(b+c)+3]=441

Ax(5x12+3)=441

Ax(60+3)=441

Ax63=441

A=441:63

A=7

C)4ab+4ac+9a=106

4x2xb+4x2xc+9x2=106

8b+8c+18=106

8b+8c=106-18

8x(b+c)=88

B+c=88:8

B+c=11