CBSE > Class 09 > Mathematics | CBSE Board | Homework Help

Perimeter = sum of all sides of triangle i.e. 42 = 18+10+c 42 = 28+c 42-28=c 14=c Then, semi - perimeter = a+b+c/2 = 18+10+14/2 = 42/2 = 21 cm. Now, you can easily find area using heron's formula

1Thank You

Yogita Ingle 4 years, 10 months ago

Given,
Side a=18cm
Side b=10cm
Perimeter=42cm=a+b+c
:. Putting value
42=18+10+c
42=28+c
42-28=c
14=c
Now,
S=(a+b+c)/2
:. Putting value
S=42/2
S=21
Now according to Heron's formula-
Area of a triangle
=√{s(s-a)(s-b)(s-c)}
:. Putting value
=√{21(21-18)(21-10)(21-14)}
=√{21(3)(11)(7)}
=√4851
=21√11cm²

1Thank You

ANSWER

If the mean of x and 1/xis M ,then the mean of x^2and 1/x^2 .find the value of the square of radius 3:5cm.

Posted by Mehak ❤️ 4 years, 10 months ago

CBSE > Class 09 > Mathematics

0 answers

ANSWER

How the class interval and size

Posted by Chethana Uday Shetty 4 years, 10 months ago

CBSE > Class 09 > Mathematics

1 answers

Dipak Gupta 4 years, 10 months ago

Cl and dize

0Thank You

ANSWER

What is the total surface area of hemisphere???

Posted by Khushi ?✨ 4 years, 10 months ago

CBSE > Class 09 > Mathematics

4 answers

Yatharth Patil 4 years, 10 months ago

3πr^2

1Thank You

Dipak Gupta 4 years, 10 months ago

4πr2h

1Thank You

Rishita Kumar 4 years, 10 months ago

4/3πr3

1Thank You

Mehak ❤️ 4 years, 10 months ago

K=(2πr^2)+(πr^2)=3πr

2Thank You

ANSWER

Show that AB>AC

Posted by Tannu Nara 4 years, 10 months ago

CBSE > Class 09 > Mathematics

1 answers

Dipak Gupta 4 years, 10 months ago

A_______________B. A__________C. So,AB>AC

0Thank You

ANSWER

77&23+43

Posted by Khushi Yadav 4 years, 10 months ago

CBSE > Class 09 > Mathematics

1 answers

Dipak Gupta 4 years, 10 months ago

72+66= 138

0Thank You

ANSWER

Find the class mark of class interval 100-200

Posted by Ritik Kumar 4 years, 10 months ago

CBSE > Class 09 > Mathematics

1 answers

Namrata Jindal 4 years, 10 months ago

Class mark =(100+200)/2 = 300/2 = 150

0Thank You

ANSWER

Define SAS

Posted by Bhavesh Patil 4 years, 10 months ago

CBSE > Class 09 > Mathematics

5 answers

Pranshu Learn 4 years, 10 months ago

SAS means side angle side it is congruency rule of triangle

0Thank You

Indian Gamer 4 years, 10 months ago

It's full form is side angle side It is a congruent rule in which two sides and included angle of a triangle is equal to othet triangle then it is congruent to other triangle

1Thank You

Arjun Prasad 4 years, 10 months ago

Side angle side is a congruence rule in which two side and angle between the sides of a triangle are congruent to other two side And angle b/w them of another triabgle

2Thank You

Kishlay Singh 4 years, 10 months ago

It is a type of criteria,which is used to congruent two Triangles.It stands for Side-Angle-Side that means if 2 sides and one angle of triangles are equal,then the triangles can be congruent by S-A-S Criteria.

2Thank You

Anushka Mallick 4 years, 10 months ago

It stands for Side angle side. It is one type of criteria

2Thank You

ANSWER

What is maths

Posted by Rajkumar Thakur 4 years, 10 months ago

CBSE > Class 09 > Mathematics