Find the sum of the measures of the interior angles of the indicated convex polygon

Mathematics

1 answer:

frozen [14]3 years ago

5 0

180(n-2)
N is number of sides
Nonagon has 9 sides.
9-2=7
7x180=1260

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A pole that is 3 m tall casts a shadow that is 1.74 m long at the same time a nearby building casts a shadow that is 50.75 m lon

bija089 [108]

87.5

Tall. /. Shadow
3 / 1.74=. X /. 50.75
Cross multiply
152.25= 3x
Divide by 3
X= 87.5

4 0

3 years ago

I need to use the Pythagorean Theorem to find X. I don’t know how to do that!!

frutty [35]

Answer:

17) x=8

18) $x=\sqrt{189}$ or $x= 3\sqrt{21}$

Step-by-step explanation:

So the rule is $a^{2} +b^{2} =c^{2}$ , "c" being the hypothenuse, or the long line that is opposite to the right angle.

17) We know that both values of x are equal to each other, which makes everything 10x easier!

$x^{2} +x^{2} =(8\sqrt{2}) ^{2}$

(by the way we know the x values are our a and b values because they are legs! the way I like to remember the legs is that they are connected to the right angle box, and therefore support the hypothenuse)

<em>simplify</em> (╥︣﹏╥)

$2x^2=8^2(\sqrt{2} )^{2}$

$2x^2=64(2)$

$2x^2=128$

$x^{2}= 128/2$

$x^{2} =64$

x=8

18) Just pretend that the flipped triangle doesn't exist. It's parallel to the other triangle with values on it, and basically servers no purpose other than being parallel to the sister triangle :)

Anyways, since we know the hypothenuse (15) but we don't know one of our leg values (x), we're going to change our equation a bit!

$c^{2} - b^{2} = a^{2}$