Question

BUNA!! ma puteti ajuta la urmatoarele ex. !ofer 40p ,Coroana+Multtumesc ! Dar vreau raspunsuri corecte., si complete in cel putin 30 min'

1) Determina numarul x: 4ori x-12<15
2)Rezolvati inecuatiile : a) x+21<4ori6 ,b) x+17>29+2ori18
3) Diferenta intre 71 si un numar natural este egala cu 41.Determinati numarul.
4) Suma a patru numere pare consecutive este 164. Determinati numerele.
5) Rezolva ecuatiile; a) x+23ori 10=11ori41-119' b) 42 ori 6+x-13ori7= 256+13ori 5' c) 74+3 ori (86-7ori3)=x+5ori(196-7 ori20) , d) 37ori24ori5-x=100-7ori 9
6)Determinati nr.natural 'x' stiind ca:
a)100ori[25-5ori(x-3)+2] :4=300
b) [(x+3):200+90] :10-10 =0

Answer 1

1)4×x-12 <15
4×x <15+12
4×x<27
x <27÷4
x poate fi 6,5,4,3,2,1,0
2)a)x+21 <4×6 b)x+17>29+2×18
x+21 <24 x+17>29+36
x <24-21 x+17>65
x <3 x>65-17
x poate fi 2,1,0 x>48
x poate fi 49,50...ect.
4)a+a+2+a+4+a+6=164
4a+12=164
4a=152
a=152÷4=38
Numerele sunt 38,40, 42, 44
5)a)x+23×10=11×41-119
x+230=451-119
x+230=332
x=332-230
x=102
b)42×6+x-13×7=256+13×5
252+x-91=256+65
252+x-91=321
252+x=321+91
252+x=412
x=412-252
x=160
c)74+3×(86-7×3)=x+5×(196-7×20)
74+3×(86-21)=x+5×(196-140)
74+3×65=x+5×56
74+195=x+280
269=x+280
280-269=x
11=x
d)37×24×5-x=100-7×9
888×5-x=100-63
4440-x=37
4440-37=x
4403=x
6)a)100×[25-5×(x-3)+2]÷4=300
[25-5×(x-3)+2]÷4=300÷100=3
25-5×(x-3)+2=3×4=12
5×(x-3)+2=25-12=13
5×(x-3)=13+2=15
x-3=15÷5=3
x=3+3=6
b)[(x+3)÷200+90]÷10-10=0
[(x+3)÷200+90]÷10=10+0=10
(x+3)÷200+90=10×10=100
(x+3)÷200=100-90=10
(x+3)=200×10=2000
x=2000-3=1997
Scuze că adurat mult să scriu eu scriu foarte încet