Question

In right triangle PQR , PQ=12 cm and QR=5cm .What is cos R?

Answer 1

cosR =
`(5)/(13)`

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 =
`(adjacent)/(hypotenuse)` =
`(QR)/(PR)` =
`(5)/(13)`