Question 19401
<font face = "courier new">
` ` ` b-a
b = ` --- 
` ` ` `a 
`
solve for b 
`<font size = 4><b>
Multiply both sides by " a ",  the LCD
`
` ` ` ` b-a
b·a = ` --- · a 
` ` ` ` `a 
`
Cancel the a's on the right
`
` ` ` ` b-a
b·a = ` --- · <s>a</s> 
` ` ` ` `<s>a</s> 
`
ba = b-a
`
Get all the terms with b's on one side and all terms without b's on the other side:
`
a = b - ba
`
Factor out b on the right
`
a = b(1 - a)
`
Divide both sides by (1 - a)
`
` a ` ` b(1-a)
----- = ------
(1-a) ` (1-a)    
`
Cancel the (1-a)'s on the right
`
` a ` ` b<s>(1-a)</s>
----- = ------
(1-a) ` <s>(1-a)</s> 
`
` a 
----- = b
(1-a)  
`
No need for the parentheses on the left:
`
`a  
--- = b
1-a 
`
Edwin