Question 1111095
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<pre>
a)  {{{x^2 + y^2}}} = {{{(x+y)^2 - 2xy}}} =  {{{16^2 - 2*3}}} =  you calculate it.


b)  {{{(x-y)^2}}} = {{{(x+y)^2 - 4xy}}} = {{{16^2 - 4*3}}} = you calculate it.
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If you want to see other similar solved problems, look into the lesson


&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/word/evaluation/HOW-TO-evaluate-expressions-involving-x%2Binv%28x%29-x2%2Binv%28x2%29-and-x%5E3%2Binv%28x%5E3%29.lesson>HOW TO evaluate expressions involving &nbsp;{{{(x + 1/x)}}}, &nbsp;{{{(x^2+1/x^2)}}}, &nbsp;{{{(x^3 + 1/x^3)}}}  &nbsp;and &nbsp;{{{(x^5+1/x^5)}}}</A>


in this site.