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Question
`4x^2+4bx-(a^2-b^2)=0`
Solution
`4x^2+4bx-(a^2-b^2)=0`
`4x^2+4bx=a^2-b^2`
`(2x)^2+2xx2x xxb+b^2=a^2-b^2+b^2=a^2-b^2+b^2` (Adding `b^2` on both sides)
`(2x+b)^2=a^2`
`2x+b=+-a` (Taking square root on both sides)
`2x+b=a or 2x+b=-a`
`2x=a-b or 2x=-a-b`
`x=(a-b)/2 or x=-(a+b)/2`
Hence, `(a-b)/2` and `-(a+b)/2` are the roots of the given equation.
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