6 books at $ 8 = (6 * 8) = 48
if he got a discount of 20%, then he paid 80%
0.80(48) = 38.40 <== what he paid
First get like things on the same side:
-5/6b - 1/2b= -2/3 - 3/4
Then find equivalent fractions to make the equation easier to solve.
-5/6b - 3/6b= -8/12 - 9/12
Then just add things together and solve.
-8/6b= -17/12
-8b= 6(-17/12)
-8b= -17/2
b= (-17/2)/-8
b= 17/16
You can then plug the answer back into the original question to make sure it is the correct answer.
X=<span><span><span><span><span>−3/</span>2</span></span>y</span>+<span>6 is the answer to your problem I think
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