Question 1168764
{{{(x+y)^2=17^2}}}

{{{x^2+y^2+2xy=289}}}

{{{167+2xy=289}}}

{{{xy=61}}}

{{{3*xy=(3)(61)}}}



----
----
What about #2 and #3?


Use #1, done here already, as a guide.  Think!   #1 and #3  are similar.  






---


#2, just a start,
{{{(x+y)^2=169}}}
{{{x^2+y^2+2xy=169}}}
substitute using the other given equation,...
...