TRIANGLE

CREATED BY :

NUR ISNAENI MARIKHAR (1511042003)

ANDI LESTARY NASIR ( 1511042013)

MATHMATICS DEPARTMENT FACULTY OF MATHMATICS AND NATURAL SCIENCES

State University of Makassar

2015

BUILD FLAT TRIANGLE

Triangle is a flat wake bounded by three sides of the dam has three vertex.

 

 Mathematician Euclid who lived around the year 300 BC (MS) find that the sum

of the three angles in a triangle on a plane is 180 degrees. This allows us to

calculate the amount one corner when the other two angles are known.

FORMULA BROAD TRIANGLE:

The formula to calculate the area of a triangle that is

L = ½.alas.tinggi

TYPES OF TRIANGLE

1. Types of Triangle Judging from The corners

Judging from the angles, the triangle is divided into three, namely:

a. Triangular taper

Acute triangle is a triangle which is great every corner is a large taper angle or

angle between 0 ° to 90 °.

 

 

in the figure, the triangleabcisa triangulartaper<A <B and<C isthe acute angle

b. Obtuse triangle

Obtuse triangle is a triangle in which one of the three corners is a large obtuse

angle or an angle between 90 ° and 180 °.

 

 

in the figure, trianglePQRisan obtuse triangle<p is anobtuse angle

c. Right triangle

Right-angled triangle is a triangle in which one angle bracket or a large angle of

90 °.

 

 in the figure, triangleABCisangledtriangle

<A =elbowor

<A =90

2. Types of Triangle Judging from Long The sides

Judging from the length of the sides, the triangle is divided into three types,

namely:

a. Scalene triangle

Scalene triangle is a triangle whose three sides are different lengths and three

different corners of magnitude.

 

in the figure, triangleABC is scalene triangle=

lengthAB=BC=AC

great<A =<B =<C

Random triangle has the following formula:

broad =

 

Where s is the half of the circumference of the triangle, namely:

s = 1/2 (a + b + c)

b. Equilateral triangle

Equilateral triangle is a triangle whose three sides of the same length.

 

 

in the figure, triangleKLMequilateral triangle

lengthKL=LM=KM

angletriangleequal, <K =<L =<M =60

Equilateral triangle has a wide following formula:

broad =

 

Where a is the side length of the equilateral triangle.

C. Isosceles triangle

Isosceles triangle is a triangle that has two sides of equal length.

 

Isosceles triangle has the following formula:

L = 2 x (1/2 x A x t)

In the isosceles triangle there will be two right-angled triangle whose height is

the result of the division line isosceles triangle.

PROBLEMS EXAMPLE :

1). Find the area of the triangle below!

 

Answer:

Is known:

a = 4 b = 6

Asked:

Area of the triangle?

area = x A x t

          

       = x 4 x 6

          

       = x 24 = 12 cm2

          

2) A triangle with the base 124cm long and 100cm high, what is the breadth?

   Answer:

Is known:

a = 124 t = 100

Asked:

Area of the triangle?

Size = a x t

              2

        = 124 x 100

                  2

        = 12400

                2

        = 6200 cm2

3). Triangle ABC is a right triangle at point A. Calculate the length of BC, if the

length AB 4 cm

and AC 3 cm long!

Answer:

Is known :

AB = 4 cm

AC = 3 cm

Asked:

BC. , , , ?

Answer:

BC2 = AB2 + AC2

BC2 = 42 + 32

BC2 = 16 + 9

BC2 = 25

BC = 5 cm

So the length of BC = 5 cm

4). ). If an isosceles triangle peak angle is 30o, how large the other angle?

  

Answer:

Large angle BAC = 300, then

Large angle ABC = BCA namely:

180-30 = 750

      2

BIBLIOGRAPHY :

Abels, M, Wijers, m, Kindt, M, Dekker, T, Burrill, G, Sim on, A N , and Cole, B.

R (2006).Operatons. In Wisconsin Center for Education Research &

Freudenthal Institute (Eds), Mathematics in Context. Chicago Encyclopedia

Britannica, Inc.

Lappan, G , Fey, J. T., Fitzgerald, W. M, Friel, S. N., & Phillips, E. D . Data

About Us: Statistics. Connected Mathematics. Boston: Perason, Prentice Hall.