Răspuns :
( 9 × a - 78 : 2 ) + 4 × 25 = 1 492
( 9 × a - 39 ) + 100 = 1 492
9 × a - 39 = 1 492 - 100
9 × a = 1 392 + 39
9 × a = 1 431
a = 1 431 : 9
a = 159
( 9 × a - 39 ) + 100 = 1 492
9 × a - 39 = 1 492 - 100
9 × a = 1 392 + 39
9 × a = 1 431
a = 1 431 : 9
a = 159
[tex](9 \times a - 78 \div 2) + 4 \times 25 = 1492 \\ (9 \times a - 39) + 100 = 1492 \\ 9 \times a - 39 = 1492 - 100 \\ 9 \times a - 39 = 1392 \\ 9 \times a = 1392 + 39 \\ 9 \times a = 1431 \\ a = 1431 \div 9 \\ a = 159[/tex]