Question 155338
I have to solve for B and I have no clue how to do this 
The teacher said it can be done in 1-2 steps 
AB-CD = BD+AC 
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You can only solve for B in terms of the other 3 variables.
Add CD to both sides
AB = BD+AC+CD
Get all terms with B on the same side by subtracting BD from both sides
AB-BD = AC+CD
Factor the terms
B*(A-D) = C*(A+D)
Divide by (A-D) to get B by itself
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B = C*(A+D)/(A-D)
That's as far as you can go.