Question 982369
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x=amount of increase
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{{{(16cm+x)(4cm+x)=160cm^2}}}
{{{64cm^2+16xcm+4xcm+x^2=160cm^2}}}
{{{x^2+20xcm-96cm^2=0}}}
{{{(x-4cm)(x+24cm)=0}}}
{{{x-4cm=0}}} {{{OR}}} {{{x+24cm=0}}}
{{{x=4cm}}} {{{OR}}} {{{x=-24cm}}}
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x-24cm gives unreasonable measurements so x=4cm
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CHECK:
{{{(16cm+4cm)(4cm+4cm)=160cm^2}}}
{{{(20cm)(8cm)=160cm}}}
{{{160cm=160cm}}}