Question

1.a)Cu cat la suta a crescut alocatia,daca era 25 lei si a devenit 32 lei.

b)Rezolvati in Z : (2x-5)(5+2x) mai mic si egal (2x+1)la 2

 

Answer 1

p/100·25=32
25p/100=32
p=32·100/25=128
128%-100%=28%
cu 28% a crescut alocatia 
verificare
28/100·25=7 lei
25+7=32 lei
2) (2x-5)(5+2x) ≤ (2x+1)²
10x+4x²-25-10x≤4x²+4x+1
4x²-4x²-4x≤25+1
-4x≤26   ·-1
x≥26/4
x≥13/2
nu are soluti pt.ca apartine multimii nr.rationale Q