The sum,S, of the internal angles of regular polygon is (n-2) 180°
Where n is the number of sides.
For the octagon n = 8, then S (8 - 2) 180° = 1080°.
Given that it is regular, each angle is 1080° / 8 = 135°
Then 4x + 12 = 135 => 4x = 135 - 12 = 123
x = 123 / 4 = 30.75 °
The volume is around 50.27
the surface area is: 75.4
the perimeter 25.13
a + (n - 1)d
a is 46, the initial.
n is the nth term, or in this case 12
d is difference, which is 4
plug this info in....
46+ (12-1)4
=90
Answer:
=4x2+12x+9
Step-by-step explanation:
(2x+3)(2x+3)
(happy to help)