Trigonometry: Find the length of side x on the right-angled triangle.

To answer this question it is best to remember SOH CAH TOA.SOH: sin(angle)=opposite (length of side opposite the angle)/hypotenuse (length).CAH: cos(angle)=adjacent (length of side next to the angle)/hypotenuse.TOA: tan(angle)= opposite/adjacent.
In a question like this you will be given an angle within the triangle, for example 60 degrees, and the length of one side, for example the hypotenuse as 13cm. If the side labeled x is adjacent to the angle then we will use CAH: cos(angle)= adjacent side/hypotenuse
So, cos60= adjacent/13Rearrange the equation to get adjacent = cos60 x 13Answer= 6.5

Answered by Molly K. Maths tutor

3598 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Find an equation of the straight line that is perpendicular to the straight line x + 3y = 7 and that passes through the point (4,9).


In a class of 30, the ratio of boys to girls is 2 : 3 , how many girls are there?


What is standard form?


16cos30° - 5tan60° = √x. Find the value of x.


We're here to help

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