Question

afla nunerele naturale a, b, c care veriifica simultan relatiile: 2a +b+c =110. a+2b+c=120. a+b+2c=130

Answer 1

Răspuns:

20 ; 30 ; 40

Explicație pas cu pas:

2a+ b+ c = 110

a+2b+ c = 120

a+ b+2c = 130

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4a+4b+4c=360   (:4)

a+b+c =90

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2a +b+c= 110

  a+b+c = 90   (-)

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a= 20

a+2b +c =120

a+  b+c = 90       (-)

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b=30

20+30+c=90

c=40