ABC is a right angled triangle. D is the point on AB such that AD = 3DB. AC = 2DB and angle A = 90 degrees. Show that sinC = k/√20 where k is an integer. Find the value of k

AB = 4DB

AC = 2DB

Find BC using Pythagoras:

BC = √(4DB)2 + (2DB)2

BC = √20DB2

= √20 DB

sinC = opp/hyp = 4DB/√20DB = 4/√20

so k = 4

TJ
Answered by Tom J. Maths tutor

14565 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

What is Pythagoras' Theorem and how is it used in exam questions?


Solve the Inequality X^2 - 2X - 8 < 0


Solve by factorisation. 2x(^2)+5x-12=0


solve x^2 + 5x +6 = 0


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences