JAMB - Mathematics (1985 - No. 41)
In \(\bigtriangleup\) XYZ, XKZ = 90O, XK = 15cm, XZ = 25cm and YK = 8cm. Find the area of \(\bigtriangleup\)XYZ
190 sq.cm
20 sq.cm
210 sq.cm
160sq.cm
320sq.cm
Explication
By Pythagoras, KZ2 = 252 - 52
KZ2 = (25 + 15)(25 - 15) = 400
KZ = \(\sqrt{400}\) = 20
area of XYZ = \(\frac{1}{2} \times 28 \times 15\)
= 210 sq. cm
KZ2 = (25 + 15)(25 - 15) = 400
KZ = \(\sqrt{400}\) = 20
area of XYZ = \(\frac{1}{2} \times 28 \times 15\)
= 210 sq. cm