Question

Given: ABCD ∥gram, BK ⊥ AD , AB ⊥ BD AB=6, AK=3 Find: m∠A, BK, AABCD

Answer 1

BK ⊥ AD

So, Δ ABK is a right triangle.

Therefore,

`BK^(2) = AB^(2) - AK^(2)`

`= 6^(2) - 3^(2)`

= 36 - 9

= 27

`Hence, BK = 3√(3)` units

Also,

cos m∠A =
`(3)/(6)`

`= (1)/(2)`

m∠A =
`60^(0)`