Answer:
Solution : Option C
Step-by-step explanation:
We have the equations r² = x² + y², x = r cos(θ), and y = r sin(θ) that can be used to solve this problem. In this case we only need the second two equations ( x = r cos(θ), and y = r sin(θ) ) as we don't need to apply the concept of circles etc here.
Given : x = - 9,
( Substitute r cos(θ) for x )
r cos(θ) = - 9,
r = - 9 / cos(θ)
( Remember that sec is the reciprocal of cos(θ). Substitute sec for 1 / cos(θ) )
r = - 9 sec(θ)
Therefore the third option is the correct solution.
(3/5 )*2000 would give you 1200, which is your answer
Since triangle BDE is right, we can check it for special rules: BD is hypotenuse = 20, and BE = 12, both divisible by 4: get 5 and 3... so it's a 3-4-5 special right triangle, the 4×4 = 16 m for side DE.
Since AD bisects angle A, I think then side DG should be congruent with DG. So then
DG = 16 m
