Area of a triangle using sineIB MYP Maths Extended: Flashcards

What these 13 flashcards ask

State the area formula for a triangle using sine.
Which angle is C in \frac12ab\sin C?
Area with sides 10 and 14 and included angle 30^\circ?
How do you find \sin C from an area?
What is the area of a parallelogram with sides a, b and included angle \theta?
Why do 30^\circ and 150^\circ give the same triangle area?
When is the area of a triangle with two fixed sides largest?
What is a bearing?
Back bearing of 040^\circ?
When do you use the cosine rule before finding an area?
When do you use the sine rule before finding an area?
How can you find the shortest distance from a vertex to a side?
What should you do at the end of a design problem?

Exam questions on Area of a triangle using sine

In triangle $ABC$ , $AB=10$ cm, $BC=14$ cm and $A\hat BC=30^\circ$ .
Find the shortest distance from $A$ to the line $BC$ .2 marks
$PQRS$ is a parallelogram with $PQ=12$ cm, $QR=9$ cm and $P\hat QR=70^\circ$ .
Find the length of the diagonal $PR$ .2 marks
A ship leaves port $A$ and sails 8 km on a bearing of $040^\circ$ to a buoy $B$ . It then sails 6 km on a bearing of $100^\circ$ to a second buoy $C$ .
Find the angle $A\hat BC$ .3 marks

Written by the Exaim team, led by Shaun Daswani (Head of Upper Secondary, Improve ME Institute; MSc Financial Mathematics, Imperial College London; BSc, UCL) and Jason Daswani (operational lead, Improve ME Institute; LSE).