Question

Determinati numerele a,b,c stiind ca:
7a+7b+7c-208=744
a=1/2 din b
C + 24 =b

Va rogg ! E urgenttt. Dau coroanaaaaa

Answer 1

7a+7b+7c-208=744
a=1/2 din b => a = b/2
c + 24 = b => c = b - 24
7a+7b+7c=744+208
7a+7b+7c=952 | :7
a + b + c = 136
a + b  = 136 - c 
(1/2)b + b  = 136 - c 
b/2 + b  = 136 - c 
b/2 + c + 24  = 136 - c 
b/2 + c  = 136 - c - 24
b/2 + b - 24 = 236 - (b-24)-24
b/2 + b - 24 = 236 - b+24-24
b/2 + b - 24 = 236 - b
b/2 + 2b = 236+24
b/2 + 2b = 260
b/2 + 4b/2 = 520/2 | · 2
5b = 520
=> b = 520/5 => b = 104
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c + 24 = b
c + 24 = 104
=> c = 104 - 24
=> c = 80
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a + b + c = 136
a + 104 + 80 = 136
=> a = 136 - 104 - 80
=> a = 136 - 184
=> a = -48
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Proba : 
-48 + 104 + 80 = 136