Question

gaseste valoarea lui a si verifica apoi rezultatul.

40x {26-2x[10+(a+2)]} = 0

Answer 1

40 x { 26 - 2 x [ 10 + ( a + 2 ) ] } = 0

26 - 2 x [ 10 + ( a + 2 ) ]  = 0 : 40 = 0

2 x [ 10 + ( a + 2 ) ]  = 26 - 0 = 26

10 + ( a + 2 ) = 26 : 2

a + 2 = 13 - 10

a + 2 = 3

a = 3 - 2

a = 1

Verific:  40 x { 26 - 2 x [ 10 + ( 1 + 2 ) ] } = 40 x ( 26 - 2 x 13 ) = 40 x 0 = 0