In ΔXYZ, ∠X = 90o, YZ = 15 cm, and XZ = 12 cm. Then find cos Y.

$\frac{2}{5}$ $\frac{4}{5}$ $\frac{3}{5}$ $\frac{3}{4}$

$\frac{3}{5}$

Using pythagoras theorem , 122 + XY2 = 152 XY = 9 cosY = \(\frac{9}{15}\)  = \(\frac{3}{5}\)