A:
1200=4x+3*(330-x)
B:
x^2+y^2=7^2
x^2+(z-y)^2=15^2
y^2+(z-x)^2=20^2
(z-y)^2+(z-x)^2=ans^2
C:
0=(x+y)%2
D:
r[n]^2+r[n+1]^2=2*n^2
E:
ΣBinom(4,i)*Binom(i+2,i-1)*i^4*(-1)^i
F:
(r-1/8)^2 = (x-1/8)^2 +y^2,
(r-1/6)^2 = x^2 +(y-1/6)^2,
(r-5/24)^2 = (x-1/8)^2 +(y-1/6)^2
ans=r
