Answer
Verified
404.4k+ views
Hint: We will use the formula of area of the triangle to calculate the required value of the area of the triangle
Formula used: $\Delta = \dfrac{1}{2} \times base \times height$ to find the area of the triangle in square meters. Height and altitude are the same in a triangle.
Complete step by step solution:
We have to find the area of a triangle whose base is given as 7.5cm and altitude is given as 4cm. So, let the triangle be $\Delta ABC$ such that :
Now we know that
Area of a $\Delta = \dfrac{1}{2} \times base \times height.$
Then, Area of $\Delta ABC = \dfrac{1}{2} \times base \times altitude$
Now in $\Delta ABC$ , base$ BC = 7.5cm$ and altitude or height $OA = 4cm$ .
Next, we will put the values of the base and height of $\Delta ABC$ in the formula for Area of $\Delta $ and get:
Area of $\Delta ABC = \dfrac{1}{2} \times base \times altitude$
$
Area Of\Delta ABC = \dfrac{1}{2} \times BC \times OA \\
Area Of\Delta ABC = \dfrac{1}{2} \times 7.5 \times 4 \\
Area Of\Delta ABC = 15c{m^2} \\
$
So we will get an area of $\Delta ABC$=$ = 15c{m^2}$ .
However the solution does not end here, since we need to find the area in square meters.
So we need to convert the area we have calculated from square centimeters to square meters.
Now,
$1c{m^2} = 1cm \times 1cm$
And,
$
1cm = 0.01m \\
\because 100cm = 1m \\
$
Then, if $1cm = 0.01m$,
$
\Rightarrow 1c{m^2} = 1cm \times 1cm \\
= 0.01m \times 0.01m \\
= \dfrac{1}{{100}}m \times \dfrac{1}{{100}}m \\
= \dfrac{1}{{10000}}{m^2} \\
= 0.0001{m^2} \\
$
If $1c{m^2} = 0.0001{m^2}$ then $15c{m^2}$ will be
$
= 15 \times 0.0001{m^2} \\
= 0.0015{m^2} \\
$
Therefore, the area of $\Delta ABC$ is $0.0015{m^2}$ , when expressed in square meters.
Hence area of the triangle with base =7.5cm and altitude = 4cm. is $0.0015{m^2}$.
Note:If the height of the triangle is not given and only the sides of the triangle are given, then we cannot use this formula. We will use Heron’s Formula to find the area of a triangle whose three sides are given to us.
For Heron’s formula first we will calculate ‘s’ which is the semi perimeter as :
$s = \dfrac{{a + b + c}}{2}$ , where a,b and c are the three sides of a triangle respectively. And then we will find the Area of $\Delta = \sqrt {s(s - a)(s - b)(s - a)} $ . This is Heron’s formula for finding the area of a triangle whose all sides are given to us.
Formula used: $\Delta = \dfrac{1}{2} \times base \times height$ to find the area of the triangle in square meters. Height and altitude are the same in a triangle.
Complete step by step solution:
We have to find the area of a triangle whose base is given as 7.5cm and altitude is given as 4cm. So, let the triangle be $\Delta ABC$ such that :
Now we know that
Area of a $\Delta = \dfrac{1}{2} \times base \times height.$
Then, Area of $\Delta ABC = \dfrac{1}{2} \times base \times altitude$
Now in $\Delta ABC$ , base$ BC = 7.5cm$ and altitude or height $OA = 4cm$ .
Next, we will put the values of the base and height of $\Delta ABC$ in the formula for Area of $\Delta $ and get:
Area of $\Delta ABC = \dfrac{1}{2} \times base \times altitude$
$
Area Of\Delta ABC = \dfrac{1}{2} \times BC \times OA \\
Area Of\Delta ABC = \dfrac{1}{2} \times 7.5 \times 4 \\
Area Of\Delta ABC = 15c{m^2} \\
$
So we will get an area of $\Delta ABC$=$ = 15c{m^2}$ .
However the solution does not end here, since we need to find the area in square meters.
So we need to convert the area we have calculated from square centimeters to square meters.
Now,
$1c{m^2} = 1cm \times 1cm$
And,
$
1cm = 0.01m \\
\because 100cm = 1m \\
$
Then, if $1cm = 0.01m$,
$
\Rightarrow 1c{m^2} = 1cm \times 1cm \\
= 0.01m \times 0.01m \\
= \dfrac{1}{{100}}m \times \dfrac{1}{{100}}m \\
= \dfrac{1}{{10000}}{m^2} \\
= 0.0001{m^2} \\
$
If $1c{m^2} = 0.0001{m^2}$ then $15c{m^2}$ will be
$
= 15 \times 0.0001{m^2} \\
= 0.0015{m^2} \\
$
Therefore, the area of $\Delta ABC$ is $0.0015{m^2}$ , when expressed in square meters.
Hence area of the triangle with base =7.5cm and altitude = 4cm. is $0.0015{m^2}$.
Note:If the height of the triangle is not given and only the sides of the triangle are given, then we cannot use this formula. We will use Heron’s Formula to find the area of a triangle whose three sides are given to us.
For Heron’s formula first we will calculate ‘s’ which is the semi perimeter as :
$s = \dfrac{{a + b + c}}{2}$ , where a,b and c are the three sides of a triangle respectively. And then we will find the Area of $\Delta = \sqrt {s(s - a)(s - b)(s - a)} $ . This is Heron’s formula for finding the area of a triangle whose all sides are given to us.
Recently Updated Pages
Three beakers labelled as A B and C each containing 25 mL of water were taken A small amount of NaOH anhydrous CuSO4 and NaCl were added to the beakers A B and C respectively It was observed that there was an increase in the temperature of the solutions contained in beakers A and B whereas in case of beaker C the temperature of the solution falls Which one of the following statements isarecorrect i In beakers A and B exothermic process has occurred ii In beakers A and B endothermic process has occurred iii In beaker C exothermic process has occurred iv In beaker C endothermic process has occurred
The branch of science which deals with nature and natural class 10 physics CBSE
The Equation xxx + 2 is Satisfied when x is Equal to Class 10 Maths
Define absolute refractive index of a medium
Find out what do the algal bloom and redtides sign class 10 biology CBSE
Prove that the function fleft x right xn is continuous class 12 maths CBSE
Trending doubts
Difference Between Plant Cell and Animal Cell
Difference between Prokaryotic cell and Eukaryotic class 11 biology CBSE
Fill the blanks with the suitable prepositions 1 The class 9 english CBSE
Change the following sentences into negative and interrogative class 10 english CBSE
Write two gases which are soluble in water class 11 chemistry CBSE
Give 10 examples for herbs , shrubs , climbers , creepers
Fill the blanks with proper collective nouns 1 A of class 10 english CBSE
What organs are located on the left side of your body class 11 biology CBSE
The Equation xxx + 2 is Satisfied when x is Equal to Class 10 Maths