What is the length of the altitude of the equilateral triangle below
What is the length of the altitude of the equilateral triangle below
Answer
Find out the altitude of the equilateral triangle .
To proof
By using the trignometric identity.
\(tan\theta = \frac{Perpendicular}{base}\)
As shown in the diagram
and putting the values of the angles , base and perpendicular
\(tan 60^{\circ} = \frac{a}{4\sqrt{3}}\)
\(tan 60^{\circ} = \sqrt{3}\)
solving
\(\sqrt{3} = \frac{a}{4\sqrt{3}}\)
\(a = \sqrt{3}\times 4 \sqrt{3}\)
As
\(\sqrt{3}\times \sqrt{3} = 3\)
put in the above
a = 4 × 3
a = 12 units
The length of the altitude of the equilateral triangle is 12 units .
Option (F) is correct .
Hence proved
Answer:
F. 12
Step-by-step explanation:
We have been given an image of a triangle and we are asked to find the length of the altitude of our given triangle.
Since we know that altitude of an equilateral triangle splits it into two 30-60-90 triangle.
We will use Pythagoras theorem to solve for the altitude of our given triangle.
\(\text{Leg}^2+\text{Leg}^2=\text{Hypotenuse}^2\)
Upon substituting our given values in above formula we will get,
\((4\sqrt{3})^2+a^2=(8\sqrt{3})^2\)
\(16*3+a^2=64*3\)
\(48+a^2=192\)
\(48-48+a^2=192-48\)
\(a^2=144\)
Upon taking square root of both sides we will get,
\(a=\sqrt{144}\)
\(a=12\)
Therefore, the length of the altitude of our given equilateral triangle is 12 units and option F is the correct choice.