Answer:
cosR = [tex]\frac{5}{13}[/tex]
Step-by-step explanation:
assuming the right triangle has ∠ Q = 90° with legs 5 and 12
then this is a 5- 12- 13 right triangle with hypotenuse PR = 13 cm
then
cosR = [tex]\frac{adjacent}{hypotenuse}[/tex] = [tex]\frac{QR}{PR}[/tex] = [tex]\frac{5}{13}[/tex]