Question 852873
{{{(-6x-7y^2)^2}}}

Means;
{{{(-6x-7y^2)(-6x-7y^2)}}}

The shortcut is actually;

Square of first term + 2 time first term times last term + square of last term
{{{(-6x)^2+(2)(-6x)(-7y^2)+(-7y^2)^2}}}
{{{36x^2+84xy^2+49y^4}}}

Thanks!

Hope that helps!

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