Clasa a v a
B) 2 • x + 23 = 91
C) 327- 3 • x = 15+ 48
D) 15 + ( x + 2) + 21 = 47
E) 2 • x + 37 = 79 - 14
F) 32 + (2 • x - 5) = 63 + 14
• = ori (de ex 4 ori 5
Plus - un avion a decolat la ora 22 si a aterizat la 6 si 15 min. Cate Min a durat zborul
Răspunsuri la întrebare
Răspuns:
b) 2•x+23=91
2•x= 91-23
2•x=68
x=68:2
x=34
c)327-3•x=15+48
327-3•x= 63
3x=327+63
x=336:3
x=112
d)15+(x+2)+21=47
(x+2)+36=47
x+2=47-36
x+2=11
x=11-2
x=9
e)2•x+37=79-14
2•x=65-37
2•x=28
x=28:2
x=14
f)32+(2•x-5)=63+14
2•x-5=77-32
2•x=45+5
x=50:2
x=25
Problema de mai sus:
9 h si 15 min.
Sper ca te-am ajutat.
2 x + 23 = 91
2 x = 91 - 23
2 x = 68
x = 68 : 2
x = 34
327 - 3 x = 15 + 48
327 - 3 x = 63
3 x = 327 - 63
3 x = 264
x = 264 : 3
x = 88
15 + ( x + 2 ) + 21 = 47
15 + ( x + 2 ) = 47 - 21
15 + ( x + 2 ) = 26
x + 2 = 26 - 15
x + 2 = 11
x = 11 - 2
x = 9
2 x + 37 = 79 - 14
2 x + 37 = 65
2 x = 65 - 37
2 x = 28
x = 28 : 2
x = 14
32 + ( 2 x - 5 ) = 63 + 14
32 + ( 2 x - 5 ) = 77
2 x - 5 = 77 - 32
2 x - 5= 45
2 x = 45 + 5
2 x = 50
x = 50 : 2
x = 25
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8 ore şi 15 minute = 8 × 60 + 15 = 480 + 15 = 495 minute