Question 55277
 p^2-4p+4=0 [Factor or use the quadratic equation]
(p-2)(p-2)=p^2-2p-2p+4=p^2-4p+4
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.or

{{{p = (-(-4) +- sqrt( (-4)^2-(4)(1)(4) ))/(2)(1)) }}}
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{{{p = (((4) +- sqrt(16-16) ))/(2)))) }}}
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{{{p = (((4) +- sqrt(0) ))/(2)))) }}}
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p=4/2=2
p=2
p-2=0
(p-2)(p-2)=p^2-4p+4