Question 1077066
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<pre>
{{{a^2 + b^2}}} = {{{(a+b)^2 - 2ab}}} = {{{20^2 - 2*40}}} = 400 - 80 = 320.
</pre>

SOLVED.


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It is the STANDARD way in which THIS problem MUST be solved.


Even do not try to find "a" and "b" explicitly and separately (although it is possible . . . ).
It would NOT be the way.