All GMAT Math Resources
Example Questions
Example Question #551 : Problem Solving Questions
An equilateral triangle has a side length of . What is the height of the triangle?
The height of an upright equilateral triangle is the perpendicular distance from the center of its base to its top. We can imagine that this line cuts the equilateral triangle into two congruent right triangles whose height is half the length of the original base and whose hypotenuse is the original side length. In these two congruent triangles, their base, which is the height of the equilateral triangle, is the only unknown side length, so we can use the Pythagorean theorem to solve for it:
Example Question #311 : Geometry
is an equilateral triangle, with a side length of . What is the height of the triangle?
We know the length of the side, therefore we can use the formula for the height in an equilateral triangle:
, where is the length of a side and the length of the height.
Therefore, the final answer is .
Example Question #1 : Calculating The Height Of An Equilateral Triangle
Given that an equilateral triangle has side lengths equal to , determine it's height in simplest form.
To solve, we must use pythagorean's theorem given that we know the hypotenuse is and one side length is . Therefore:
Example Question #1 : Calculating The Perimeter Of An Equilateral Triangle
The area of an equilateral triangle is . What is the perimeter of ?
The area is given, which will allow us to calculate the side of the triangle and hence we can also find the perimeter.
The area for an equilateral triangle is given by the formula
, where is the length of the side of the triangle.
Therefore, , where is the area.
Thus , and the perimeter of an equilateral triangle is three times the side, hence, the final answer is .
Example Question #2 : Calculating The Perimeter Of An Equilateral Triangle
A given equilateral triangle has a side length of . What is the perimeter of the triangle?
Not enough information provided.
An equilateral triangle with a side length has a perimeter .
Given:
,
.
Example Question #312 : Geometry
A given equilateral triangle has a side length of . What is the perimeter of the triangle?
An equilateral triangle with a side length has a perimeter .
Given:
,
.
Example Question #2 : Calculating The Perimeter Of An Equilateral Triangle
A given equilateral triangle has a side length of . What is the perimeter of the triangle?
Not enough information provided.
An equilateral triangle with a side length has a perimeter .
Given:
,
.
Example Question #3 : Calculating The Perimeter Of An Equilateral Triangle
Given the following regarding Triangle .
I)
II) Side is equal to light-years
What is the length of side ?
light years
light years
light years
light years
light years
light years
The trick to this one is to carefully put together what you are given.
We know that two of our angles are equal to 60 degrees. This means that the last angle is also 60 degrees. This make HFT an equilateral triangle.
Equilateral triangles always have equal sides and equal angles, so our last side has to be 7 light years as well.
Example Question #321 : Geometry
Calculate the perimeter of an equilateral triangle whose side length is .
The perimeter of an equilateral triangle is:
Thus.
Example Question #322 : Geometry
Find the perimeter of an equilateral triangle whose side length is .
To find the perimeter, you must multiply the side length by . Thus,