In the figure, YXZ = 30o, XYZ = 105o and XY = 8cm. Calculate YZ

Mathematics

JAMB 1990

In the figure, YXZ = 30^o, XYZ = 105^o and XY = 8cm. Calculate YZ

A. 16\(\sqrt{2}\)cm
B. 8\(\sqrt{2}\)cm
C. 4\(\sqrt{2}\)cm
D. 22cm

WAEC and NECO CBT Software for Computers and Laptops - 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

WAEC and NECO CBT App for Mobile Devices - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now

Correct Answer: Option C

Explanation

yzx + 105^o + 30^o = 180^o

yzx = 180 - 155 = 45^o

\(\frac{yz}{sin 30^o} = \frac{8}{sin 45^o}\)

yz = \(\frac{8 \sin 30}{sin 45}\)

= 8(\(\frac{1}{2}) = \frac{8}{1} \times \frac{1}{2} \times \frac{\sqrt{2}}{1}\)

= 4 \(\div\) \(\frac{1}{\sqrt{2}}\)

= 4\(\sqrt{2}\)cm

Previous Next

Go back to Maths classroom

Report an Error Ask A Question Download App