Answer:
Step-by-step explanation:
a) A square is a rectangle. True
Reason: Property of Rectangle: (i) Opposite sides are equal and parallel. (ii) Each angle is 90 (iii) Diagonals are equal and bisect each other.
A square hold all these properties. A square is a rectangle.
b) A polygon with 21 sides has 432 possible diagonals. False
Reason: Number of diagonals of a polygon = 
n --> number of sides of a polygon.
=
= 189 diagonals
c) All three angles in an Isosceles triangle are equal. False
Reason: In an isosceles triangle, two angles are equal.
If three angles are equal, then that is an equilateral triangle.
d) The measures of the exterior angles of a nonagon, a nine-sided figure, have a sum of 360°. True.
Reason: The sum of measures of the exterior angles of any polygon is 360
Non linear means not a straight line so answer C or the third answer.
Yes
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Answer: first one =109360044xy−36453348x−2, 2nd,=3037778998,last one,=1968480790
Step-by-step explanation:Evaluate for x=3x,y=6y−2
33x(2025186)(6y−2)−2
33x(2025186)(6y−2)−2
=109360044xy−36453348x−2
Evaluate for x=20,y=25
(3)(20)(2025186)(25)−2
(3)(20)(2025186)(25)−2
=3037778998
because 18 is by itself i just did Evaluate for x=18,y=18
(3)(18)(2025186)(18)−2
(3)(18)(2025186)(18)−2
=1968480790