Consider the right angled triangle with vertices labelled a, b, c. Angle A = 60°, Angle B = 90°, length ab=4cm, length ac=xcm. If cos60° = 0.5, work out the value of x.

The first thing to do in such a question is to draw out the information you have been given. Not only does this help to process the question again, so that no vital information is missed, but also makes it a lot easier to see how to go about solving the problem.The trigonometric rule of 'SOH-CAH-TOA' can then be applied. My useful hint to remember this is 'Silly Old Hitler, Caused Awful Havoc, Too Our Armies'In this question we are given information on the Cosine, Adjacent and Hypotenuse. Therefore 'CAH' is the part we need. (Cos60° = adjacent/hypotenuse) When we sub in the values given, we see 0.5=4/x, which can be rearranged to x= 4/0.5, so x=8cm.

RR
Answered by Rebecca R. Maths tutor

4629 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

How do I expand (x-2)(3x+3) into a quadratic?


Block 1 is 24mm long. Block 2 is 32mm long. Vignesh joins some type 1 blocks together to make a straight row. He then joins some type 2 blocks together to make a straight row of the same length. (a) Write down the shortest possible length of this row.


5 tins of soup have a total weight of 1750 grams. 4 tins of soup and 3 packets of soup have a total weight of 1490 grams. Work out the total weight of 3 tins of soup and 2 packets of soup.


Expand 4e(e + 2)


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2025 by IXL Learning