Lengths of two sides of the triangle and the angle between them are known. Find the length of the third side and the area of the triangle.

We don't know what type of a triangle we're considering here. Therefore the universal and quickest solution to the first problem is use of the cosine rule, which states that for a triangle with sides a,b and c and the angle θ between sides “a” and “b”:


To find the area of the triangle we should use the formula:

Szymon K. GCSE Further Mathematics  tutor, IB Further Mathematics  tu...

4 months ago

Answered by Szymon, a GCSE Further Mathematics tutor with MyTutor

Still stuck? Get one-to-one help from a personally interviewed subject specialist


£18 /hr

Rebecca S.

Degree: Geography (BSc) (Bachelors) - Edinburgh University

Subjects offered: Further Mathematics , Maths+ 3 more

Further Mathematics
Extended Project Qualification
-Personal Statements-

“Hey! I am a final year Geography student at the University of Edinburgh with a passion for combining geography and maths - the greatest subjects on Earth! I am currently involved in a number of projects such as a peer-assisted learning...”

£18 /hr

Robert F.

Degree: Mathematics (Bachelors) - Nottingham University

Subjects offered: Further Mathematics , Maths

Further Mathematics

“About Me: I am a mathematics student at the University of Nottingham. I've loved maths and science for my life and I hope that my tutorials will encourage you to do the same. I'm sociable and friendly and have tutored maths throughout ...”

MyTutor guarantee

£20 /hr

Elizabeth H.

Degree: Natural Science (Masters) - Durham University

Subjects offered: Further Mathematics , Physics+ 2 more

Further Mathematics

“Hi! I'm a Natural Sciences student at Durham University studying Physics and Chemistry. I love learning science and applying it to the real world as well as exam and homework questions, and would love to help you do the same!I tutore...”

About the author

£20 /hr

Szymon K.

Degree: Mechanical Engineering (Masters) - Manchester University

Subjects offered: Further Mathematics , Physics+ 1 more

Further Mathematics

“About me: I am a student pursuing my degree in Mechanical Engineering at the University of Manchester. Ever since I can remember I have always been passionate about passing my knowledge to others. As a tutor I taught people of differen...”

You may also like...

Other GCSE Further Mathematics questions

Solving equations with unknown in both sides

How do you use derivatives to categorise stationary points?

What is differentiation used for?

How do I know I can multiply two matrices and if so, how do I do it?

View GCSE Further Mathematics tutors


We use cookies to improve our service. By continuing to use this website, we'll assume that you're OK with this. Dismiss