Question

si: a/2 = b/3 = c/4;       2a+b-c=15

hallar "bc"

Answer 1

2a + b - c  = 15

b = 15 + c - 2a

 

si

a/2 = b /3

3.a = 2.b

a = 2b/3

 

b = 15 +c - 2(2b/3)

b = 15 +c - 4b/3

b + 4b/3 = 15 +c

7b/3 = 15 + c                 b/3 = c/4 → c = 4b/3

7b/3 = 15 + 4b/3

7b/3 - 4b/3 = 15

3b/3 = 15

b = 15

 

entonces

a = 2b/3 → a = 2.15/3 → a = 10

c = 4b/3 → c = 4.15/3 →  c = 20

 

así que

bc = 15 * 20

bc= 300

 

espero que te sirva, salu2!!!!