Question

Afla valoarea lui a , in fiecare caz :35<4 x 9+a<40. 40≤6 x 8-a≤45

Answer 1

35< 4*9 +a < 40

35< 36 + a < 40

35-36 < a <40-36

-1 < a <4

=> a apartine intervalului (-1,4)

40 <= 6*8 - a <=45

40<= 48 - a <= 45

-8 <= -a <= -3 |*(-1)

8>=a>=3

=> a apartine intervalului [3,8]