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such that 
for all real number 
and 
be a scalene triangle with point 
and 
on the plane such that 
is an equilateral . Let 
intersect 
and 
at 
and 
respectively and 
intersect 
and 
at 
and 
respectively .
, point 
on 
satisfies 
and 
.
be the point where the perpendicular from 
to line 
meets the angle bisector of 
.
holds. is an isosceles triangle.
be a positive integer such that 
.
.
over 
. Ignore "pathological" solutions.[/quote]
![\[\lfloor x \rfloor\]](http://latex.artofproblemsolving.com/d/3/f/d3f8facf62413e1f17c89b9c183a8735c2defe8b.png)
denote the greatest integer less than or equal to x . What is the sum of the squares of the real numbers x for which ![\[ x^2 - 20\lfloor x \rfloor + 19 = 0 \]](http://latex.artofproblemsolving.com/f/a/9/fa96f2d6217a16029e5f03499e0a83deffdfa28a.png)
of the pizza, where 
is a positive integer. Find .
Is there an elegant way to prove this?
with bases and 
satisfying 
. Let 
be the midpoint of . Let the point lie inside such that 
and 
. Prove that if 
, then the quadrilaterals 
and 
have the same area.
with bases and satisfying . Let be the midpoint of . Let the point lie inside such that and . Prove that if , then the quadrilaterals and have the same area.
and 
Prove that
Prove that
![\[\mathcal{P}(x) = x^{108}+x^{102}+x^{96}+2x^{54}+3x^{36}+4x^{24}+5x^{18}+6\]](http://latex.artofproblemsolving.com/e/b/2/eb28918359848dd07784a3c2c6a34b934743c016.png)
be 
.![\[\dfrac{r_1^6+r_2^6+\dots+r_{108}^6}{r_1^6r_2^6+r_1^6r_3^6+\dots+r_{107}^6r_{108}^6}\]](http://latex.artofproblemsolving.com/3/1/5/315341a7adf35bc04e40ee0685a011c9f7b76115.png)
without Newton Sums.
.
.
.
,
because 
,
is cyclic.
and line 
.
and 
,
are collinear, and 
by 
.
for example, we calculate:![\[\frac{BC}{XC}=\frac{MN}{XN}=\frac{DN}{XN}=\frac{DP}{XC}\]](http://latex.artofproblemsolving.com/d/8/1/d818d57447b5f05330a650228b7e4a4c13d422ee.png)
The last equality follows by 
concyclic. 
don't intersect" the theorem remains true.