Answer:
22
74
Step-by-step explanation:
A <span>dodecagon has 12 sides
Sum of the interior angles = (12 - 2) x 180 = 1800</span>°
One interior angle = 1800 ÷ 12 = 150°
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Answer : 150°
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Answer:
The method of solving "by substitution" works by solving one of the equations (you choose which one) for one of the variables (you choose which one), and then plugging this back into the other equation, "substituting" for the chosen variable and solving for the other. Then you back-solve for the first variable.
Step-by-step explanation:
We have the base measurement for the triangles composing the sides. We need their altitude.
Imagine a right triangle with these sides:
(1) from the apex of the pyramid to the point on the base directly underneath it (471 ft);
(2) from the middle of base edge to the point underneath the apex (half of 708 ft = 354 ft);
(3) the hypotenuse, the altitude of a triangular side.
Using the Pythagorean Theorem, we find the hypotenuse to be
√(471^2 + 354^2) = about 589.2 feet
Now we add up the four triangles' areas. Each is base * altitude / 2, so:
4 x 708 x 589.2 / 2
= 2 x 708 x 589.2
= 834,307.2 square feet, the lateral area.
