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Algebra manipulation. Thank you! My answer is - 8/5 but I want to make sure :)

Algebra manipulation. Thank you! My answer is - 8/5 but I want to make sure :)-example-1
User Feepk
by
7.6k points

1 Answer

4 votes

Start with


(2a+3b)/(a+b)=7

Assuming
a\\eq -b, multiply both sides by
a+b


2a+3b = 7a+7b

Solve for
a


5a = -4b \iff a = -(4b)/(5)

Substitute this value for
a in the desired expression:


(2a)/(b) = ((-8b)/(5))/(b) = -(8)/(5)

You were correct! :)

User Sniurkst
by
8.0k points