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Find the value of b/a if a+1/b-1=5/1 and a-1/b+1=1/1

User Zhe Li
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1 Answer

2 votes

Answer:

1/2

Explanation:

You want the value of b/a when (a+1)/(b-1)=5/1 and (a-1)/(b+1)=1/1.

Solution

The latter equation tells you ...

a -1 = b +1

b = a -2

Then the first equation tells you ...

a +1 = 5(b -1)

a +1 = 5(a -2 -1) substitute for b

a +1 = 5a -15 . . . . eliminate parentheses

16 = 4a . . . . . . . . add 15 -a

4 = a . . . . . . . . . divide by 4

b = a -2 = 4 -2 = 2 . . . . find the value of b

b/a = 2/4 . . . . . . . . . . find the desired ratio

b/a = 1/2

User Pmohandas
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