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The answer to each word problem is scalene because each triangle created has different side lengths. 
skiers behind a boat creating a triangle
Boat
A
B
Two children are skiing behind a boat. Child A has 45 foot long rope, and child B has a 50 foot rope. If they remain 10 feet apart,which of the following triangles is created? Isosceles,Scalene,Equilateral
carpenters creating a 3 4 5 triangle
Carpenters are laying a foundation to a house, and use an old trick. They create a triangle using a 3,4, and 5 foot long piece of lumber. This combination creates a 90 degree angle for the foundation. Which of the following triangles was created? Isosceles,Equilateral,Scalene

Scalene triangle word problems

 * A scalene triangle has three sides of different lengths, which results in three angles of different angle measures.












*Like all triangles, the angles of a scalene add up to 180 degrees.







*A right triangle can be a scalene triangle, but an isosceles triangle cannot because it has two equal sides.









*The vertex of a scalene triangle is the point where two lines meet and form a corner. Like every triangle a scalene has three vertices.









*Any side of a scalene triangle can be the base.

*A 30-60-90 right triangle is a scalene triangle; however a 45-45-90 is not.










*A scalene does not have a line of symmetry. If you can fold an image or object ,and both sides exactly match, then you can draw a “line of symmetry.”






*The altitude is measured by drawing a perpendicular line from the base to the opposite vertex.






*There can be three different altitudes depending on the base used.

*The three altitudes of a scalene triangle intersect at a point called the orthocenter.


orthocenter
scalene triangle orthocenter
video tutorial scalene triangles

Definition Scalene Triangle

scalene triangle area
Transcript


Welcome to MooMooMath. Today we are talking about Scalene Triangles. A scalene triangle is one in which all three angles are different. So let’s look at two examples. I’m going to mark these triangles 3 inches, 4 inches, and 5 inches. All three sides are different lengths. This triangle over here is marked such that all three sides are the same. The mark on the side represents equal lengths. This is actually an equilateral triangle. Now let’s look at a scalene triangle based on angles. You have a forty five degree angle, a forty five degree angle, and a ninety degree angle, and over here you have a 60 degree angle, a 30 degree angle, and a ninety degree angle. So based on angles which of these is a scalene angle? This one here (circles the triangle with 60, 30, 90 degree angles) because all three angles are different or all three sides are different. The other triangle these two angles are the same meaning these two legs are the same so this one is actually what they call an isosceles triangle. So let’s look at the rules. The definition is all sides are different lengths and all angles are different measures. So our 3, 4, 5, is our example. Hope this video was helpful.

Scalene Triangle-7th Grade Math

triangle 25 110 by 4 degrees/definition scalene triangle
scalene triangle 8 x 10 x 6

Scalene Triangle

This scalene triangle has three sides with different lengths

A right triangle can be a scalene triangle
This scalene triangle has three angles with different measures,which creates three different side lengths.




Scalene triangle properties

Finding the area of a Scalene Triangle

Find the area of a scalene triangle using 1/2 base x height
Height
Base
​Any side can be used as the base. However if the height is given, the base will be perpendicular to the height

Finding the perimeter of a Scalene Triangle

area scalene triangle
Height not known
Base
a
If the height is unknown you can use Heron's Formula
herons formula
b
c
heron formula scalene triangle
Height not known
Base
a
b
c
Find the perimeter of a scalene triangle using   a +b+c 
(In other words just add the length of all three sides.)

Scalene triangles in real life

roof truss scalene triangle
Scalene Triangle
Roof Truss
scalene triangle real life bicycle
scalene triangle realcar framee
Scalene triangles are used in construction, auto frames, bike frames,bridges and many other areas.
Let's look at some examples of Scalene Triangles
Common Core Standards   6.G.1    7.G.2 6th Grade Math  7th Grade Math
scalene triangle 3 different angles and side lengths
triange angles add to 180 degrees
right triangle
altitude of a triangle
triangle has three vertexs
a right triangle can be a scalene triangle
no line of symmetry (scalene triangle)
Two sides of every 45 45 90 are equal.
Notice, when cut in half, the two halves of the scalene triangle are not mirror images.
Vertex
Vertex
Vertex
scalene triangles graphic with balloons
Notice the right triangle has different side lengths.