The altitude of an equilateral triangle is 5 cm. what is the length of a side of the triangle?

Mathematics

1 answer:

Grace [21]3 years ago

3 0

Answer:

The length side of the triangle is $\frac{10\sqrt{3}}{3}\ cm$

Step-by-step explanation:

we know that

The equilateral triangle has three equal sides and three equal internal angles of measure of 60 degrees each.

Let

b------> the length side of the equilateral triangle

Applying Pythagoras theorem

$b^{2}=(b/2)^{2}+5^{2}\\\\ b^{2}-(b/2)^{2}=25\\\\ (3/4)b^{2}=25\\ \\b^{2} =25*4/3\\ \\b=\frac{10}{\sqrt{3}}\ cm\\ \\b=\frac{10\sqrt{3}}{3}\ cm$

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Can i get some help with this pls

qwelly [4]

Answer:

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Step-by-step explanation:

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4 0

2 years ago

Read 2 more answers

What's the area of this rectangle?

Bess [88]

well, the assumption is that is a rectangle, namely it has two equal pairs, so we can just find the length of one of the pairs to get the dimensions.

hmmmm let's say let's get the length of the segment at (-1,-3), (1,3) for its length

and

the length of the segment at (-1, -3), (-4, -2) for its width

$\bf ~~~~~~~~~~~~\textit{distance between 2 points} \\\\ (\stackrel{x_1}{-1}~,~\stackrel{y_1}{-3})\qquad (\stackrel{x_2}{1}~,~\stackrel{y_2}{3})\qquad \qquad d = \sqrt{( x_2- x_1)^2 + ( y_2- y_1)^2} \\\\\\ \stackrel{length}{L}=\sqrt{[1-(-1)]^2+[3-(-3)]^2}\implies L=\sqrt{(1+1)^2+(3+3)^2} \\\\\\ L=\sqrt{4+36}\implies L=\sqrt{40} \\\\[-0.35em] ~\dotfill$

$\bf (\stackrel{x_1}{-1}~,~\stackrel{y_1}{-3})\qquad (\stackrel{x_2}{-4}~,~\stackrel{y_2}{-2})\qquad \qquad d = \sqrt{( x_2- x_1)^2 + ( y_2- y_1)^2} \\\\\\ \stackrel{width}{w}=\sqrt{[-4-(-1)]^2+[-2-(-3)]^2}\implies w=\sqrt{(-4+1)^2+(-2+3)^2} \\\\\\ w=\sqrt{9+1}\implies w=\sqrt{10} \\\\[-0.35em] ~\dotfill\\\\ \stackrel{\textit{area of the rectangle}}{A=Lw}\implies \sqrt{40}\cdot \sqrt{10}\implies \sqrt{400}\implies \boxed{20}$