SOLUTION: If a + 2b = 3c and 2a + 4b + c = 56 what is the value of c? (A) -12 (B) -4 (C) 8 (D) 12 (E) 24

Algebra ->  Equations -> SOLUTION: If a + 2b = 3c and 2a + 4b + c = 56 what is the value of c? (A) -12 (B) -4 (C) 8 (D) 12 (E) 24      Log On


   

Question 1202588: If a + 2b = 3c and 2a + 4b + c = 56 what is the value of c?
(A) -12
(B) -4
(C) 8
(D) 12
(E) 24
Answer by greenestamps(13198) About Me  (Show Source):
You can put this solution on YOUR website!


(1) a+2b = 3c
(2) 2a+4b+c = 56

In the second equation, "2a+4b" is "a+2b" times 2; and the first equation gives us the value of "a+2b" in terms of c:

2a+4b+c = 56
2(a+2b)+c = 56
2(3c)+c = 56
6c+c = 56
7c = 56
c = 8

ANSWER: (C) 8