Question 1055746
Key is The isosceles triangle ABE.  Side AB is congruent to side BE.  The angle at B, on interior, is  90+60=150 degrees.


Upper interior angle at A is 60 degrees, but let this be the sum of your x plus y.
{{{x+y=60}}}.


Now back to the isosceles triangle ABE.  The TWO base angles each are of measure y.
You already know the 150 degrees at B.
{{{2y+150=180}}}
{{{2y=30}}}
{{{highlight(y=15)}}}


Now ready to find x.
Again, because equilateral, same as equiangular triangle, 
{{{x+y=60}}}
{{{x=60-x}}}
{{{x=60-15}}}
{{{highlight(x=45)}}}