Answer:
H. the number of orchestra seat is 900
Step-by-step explanation:
Step one:
let the number of orchestra seat be x
and balcony seat be y
cost of orchestra= $50 each
cost of balcony =$40 each
total tickets= 1500
x+y= 1500----------1
amount earned= $69000
50x+40y=69000--------2
The system of equation for the situation is
x+y= 1500----------1
50x+40y=69000--------2
from 1, x=1500-y
put this in equation 2
50(1500-y)+40y=69000
75000-50y+40y=69000
-10y=69000-75000
-10y=-6000
divide both sides by -10
y=-6000/-10
y=600
put y= 600 in equation 1
x+600= 1500
x=1500-600
x=900
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.
<span>the answer is 21 if that's a choice
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She used the diameter instead of the radius :) instead of cubing 8 she should’ve cubed 4