Please do not give the full answer! I just need some guidance
Consider the two expressions $(x + y)^2$ and $x^2 + y^2$. Grogg thinks that these two expressions are equal for all real numbers $x$ and $y,$ but Lizzie disagrees! Let's get to the bottom of it. a) Evaluate $(x + y)^2$ and $x^2 + y^2$ when $x = 5$ and $y = 12.$ b) For which values of $x$ and $y$ does $(x + y)^2$ equal $x^2 + y^2?$ For which values of $x$ and $y$ does $(x + y)^2$ not equal $x^2 + y^2?$
For (a) simply substitute the values x = 5 and y = 12 into both expressions and calculate the results.
For (b) set (x+y)2 = x2 + y2 then expand the left hand side and simplify the resulting equation. You will then have a condition that must be satisfied for the two ex[ressions to be equal.