##
**Area of
triangle**

Total surface
covered by a triangle is called the area of triangle. To find the area of a
triangle we can do the following activities:

i. Take a
paper in triangle shape of base (b) and height (h) as shown in the figure.

ii. Cut
horizontally through middle of the perpendicular as shown in figure.

iii. Cut
upper part into two small triangles through perpendicular as shown in the
figure.

iv. Arrange the
small triangles in one place to form a rectangle ABCD as shown in the figure.

v. The
rectangle ABCD so formed will have the length equal to b and breadth equal to
h/2 as shown in the figure.

∴ Area of Δ = Area of rectangle ABCD

= BC × CD

= b × h/2

= ½ × b × h

∴

*Area of**Δ = ½ × b × h*

###
**Area
of a right angled triangle**

When
the triangle is a right angled triangle then height (h) = perpendicular (p),
therefore the area of triangle = ½ × base × perpendicular

i.e area of

*Δ = ½ × b × p*

###
**Area
of an equilateral triangle**

In
the given figure, ΔABC is an equilateral triangle and AM⊥BC.

###
**Area
of an isosceles triangle**

In
isosceles ΔABC, AB = AC = a and base BC = b

###
**Area
of scalene triangle**

If a,
b and c are three sides of a scalene triangle then

###
*Workout Examples*

*Workout Examples*

*Example 1: Find area of the triangle given below:*

*Solution:*

*From the figure,*

*Base (b) = 12 cm*

*Height(h) = 6 cm*

*we know,*

*Area of triangle = ½ × b × h*

*= ½ × 12cm × 6 cm*

*= 36 cm*^{2}

*Example 2:*

*Find area of the triangle given below:*

*Solution:*

*Given figure is an equilateral triangle where*

*a = 6 cm*

*we know,*

*Example 3:*

*Find the area of the triangle given below:*

*Solution:*

*Given figure is an isosceles triangle where*

*Base(b) = 8 cm*

*Two equal sides (a) = 5 cm*

*we know,*

*Example 4: Find the area of the triangle ABC given below.*

*Solution:*

*In triangle ABC,*

*a=10cm, b=8cm and c=6cm*
## No comments: