2.3s + 4.6h = 4232
s + h = 1030
h = 1030 - s
2.3s + 4.6(1030 - s) = 4232
2.3s + 4738 - 4.6s = 4232
4738 - 4232 = 4.6s - 2.3s
506 = 2.3s
s = 220
h = 1030 - s
h = 1030 - 220 = 810
there were 810 downloads of the high-quality version
2. 
3. 
7. CPCTC
8. Theorem: If opposite sides of a quadrilateral are both parallel and congruent, then the quadrilateral is a parallelogram.