Jessie saw this median as she rode to school. The height of each triangle in the median is 7 feet and the base is 5 feet. Jessie wondered about the area of each triangle. If there are seven triangles in a row, what is the total area of all seven triangles?
In this concept, you will learn to find the dimensions and area of triangles.
Area of a Triangle
The base is the area at the bottom of the triangle opposite the vertex or top point. When finding the area of triangles, remember that the height of a triangle is always perpendicular to the base. The height is not necessarily a side of the triangle; this happens only in right triangles, because the two sides joined by a right angle are perpendicular.
You can see in the right triangle above that the left side is also the height of the triangle. It is perpendicular to the base. The equilateral triangle has a dotted line to show you the measurement for the height of the triangle.
Let’s look at an example.
Find the area of the triangle below.
The answer is 88.
You can also use this same formula to figure out a missing dimension of the triangle. This is possible if you are given the area and one dimension to start with. Then you can use the formula, substitute the values, and solve for the missing dimension.
Let’s take a look at an example.
Earlier, you were given a problem about the triangles.
Each of the seven triangles has a base length of 5 feet and a height of 7 feet.
Then, since there are 7 triangles, multiply this area by 7.
The answer is 122.5.
The answer is 27.
Find the area of each triangle described below.
Find the missing dimension for each triangle given the area and one other dimension.