WAEC and NECO CBT App for Mobile Devices - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now
Your School's Whatsapp Group - Join Us now

If two angles of a triangle are 30° each and the longest side is 10cm. Calculate...

Mathematics
JAMB 1993

If two angles of a triangle are 30° each and the longest side is 10cm. Calculate the length of each of the other sides.

  • A. 5cm
  • B. 4cm
  • C. 3√3 cm
  • D. \(\frac{10\sqrt{3}}{3}\)cm
WAEC and NECO CBT Software for Computers and Laptops - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now
Post UTME Past Questions Agent
WAEC and NECO CBT App for Mobile Devices - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now
Correct Answer: Option D
Explanation

Let each of the unknown side be x.

\(10^{2} = x^{2} + x^{2} - 2(x)(x) \cos 120\)

\(100 = 2x^{2} - 2x^{2} \cos 120\)

\(100 = 2x^{2} + x^{2} = 3x^{2}\)

x = \(\sqrt{\frac{100}{3}}\)

= \(\frac{10}{\sqrt{3}}\) x \(\frac{\sqrt{3}}{\sqrt{3}}\)

x = \(\frac{10\sqrt{3}}{3}\)cm


Report an Error Ask A Question Download App
Your School's Whatsapp Group - Join Us now
Post-UTME Past Questions - Original materials are available here - Download PDF for your school of choice + 1 year SMS alerts
Post UTME Past Questions Agent

Contributions ({{ comment_count }})

Please wait...

{{ settings.no_comment_msg ? settings.no_comment_msg : 'There are no comments' }}

Quick Questions

Post your Contribution

Please don't post or ask to join a "Group" or "Whatsapp Group" as a comment. It will be deleted. To join or start a group, please click here

{{ quote.posted_by.display_name }}
{{ settings.form_textarea_description }}
 
Your School's Whatsapp Group - Join Us now
WAEC and NECO CBT Software for Computers and Laptops - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now
Post UTME Past Questions Agent
WAEC and NECO CBT App for Mobile Devices - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now
Post-UTME Past Questions - Original materials are available here - Download PDF for your school of choice + 1 year SMS alerts
Your School's Whatsapp Group - Join Us now
Post UTME Past Questions Agent
Post-UTME Past Questions - Original materials are available here - Download PDF for your school of choice + 1 year SMS alerts
WAEC and NECO CBT App for Mobile Devices - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now