Part 1:
We have the following expression:
(3-6n5-8n4) - (- 6n4-3n-8n5)
Rewriting we have:
3-6n5-8n4 + 6n4 + 3n + 8n5
Adding similar terms we have:
2n5 - 2n4 + 3n + 3
Part 2:
We have the following equation:
4x2-2x-5 = 0
Using resolver we have to:
x = (- b +/- root (b2 - 4ac)) / (2a)
The solutions are:
x1 = 1/4 - root (21) / 4
x2 = 1/4 + root (21) / 4