a.
\(\Leftrightarrow x^2-2^2-\left(x^2+5x-3x-15\right)=0\)
\(\Leftrightarrow x^2-4-x^2-5x+3x+15=0\)
\(\Leftrightarrow11-2x=0\)
\(\Leftrightarrow2x=11\)
\(\Rightarrow x=\dfrac{11}{2}\)
b.
\(\Leftrightarrow x^2-2x-3x+6-\left(x^2-5x+x-5\right)=0\)
\(\Leftrightarrow x^2-2x-3x+6-x^2+5x-x+5=0\)
\(\Leftrightarrow11-x=0\)
\(\Rightarrow x=11\)
`(x+2).(x-2)-(x-3).(x+5)=0`
`x^2 - 4 - x^2-2x+15=0`
`-2x+11=0`
`-2x=-11`
`x=(-11):(-2)`
`x=11/2`
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` (x-3).(x-2)-(x+1).(x-5)=0`
`x^2 -5x+6 -x^2 +4x+5=0``-x+11=0``-x=-11``<=> x = 11`a) (x+2)(x-2) -(x-3) (x+5) =0
=> x² - 2² -(x² +5x -3x-15) =0
=> x² - 2² - 2x -15=0
=> 11-2x=0
=> x=11/2