Question

Someone please answer​

Answer 1

b = 8

Explanation:

cos Θ =
`(adjacent)/(hypotenuse)` =
`(PQ)/(QR)` =
`(b)/(14)`

given cos Θ =
`(4)/(7)` , then equate the 2 expressions , that is

`(b)/(14)` =
`(4)/(7)` ( cross- multiply )

7b = 56 ( divide both sides by 7 )

b = 8