Question 862311
{{{ 100b^2 + 140b + 49 }}}
{{{ ( 10b )^2 + 2*10*7*b + 7^2 }}}
{{{ ( 10b + 7 )^2 }}}
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Note that if I say:
{{{ 10b = x }}}
{{{ 7 = y }}}
Then I have:
{{{ x^2 + 2*x*y + y^2 = ( x + y )^2 }}}
{{{ ( x + y )^2 = ( 10b + 7 )^2 }}}
which is the answer I got