Question

(PROBABILITIE) please explain it as I need it for revision.

Answer 1

see explanation

Explanation:

(a)

Using Pythagoras' identity in right triangle ABC, that is

AC² = AB² + BC² = 3² + 5² = 9 + 25 = 34 ( take the square root of both sides )

AC =
`√(34)` ≈ 5.83 cm

(b)

Using the tangent ratio in right triangle ACD

tanACD =
`(opposite)/(adjacent)` =
`(AD)/(AC)` =
`(4)/(5.83)`, thus

∠ACD =
`tan^(-1)`(
`(4)/(5.83)`) ≈ 34.5°