Answer:
D
Step-by-step explanation:
To find conjecture about regular polygon, use the formula

Where, n = number of sides of the regular polygone
1) Triangle
n =3
So, Conjecture of the triangle =

= 120
2) Square
n =4
So, Conjecture of the square =

= 90
3) Pentagone
n = 5
So, Conjecture of the pentagon =

= 72
4) Hexagone
n = 6
So, Conjecture of the pentagon =

= 60.
Sorry man, don’t know it, hopefully you get someone who knows
Answer:
10x² - 14xy -6y
Step-by-step explanation:
5x(2x-y)-3y(2+3x)
10x²-5xy-6y-9xy
10x² - 14xy - 6y