An astronomer knows the distances from herself to stars AAA and BBB, as well as the distance between them. The distances are 450450450, 400400400, and 909090 light years (\text{l. y.}l. y.start text, l, point, y, point, end text) respectively.
If the astronomer's telescope is currently pointed at star AAA, how many degrees must she rotate her telescope to see star BBB?
Do not round during your calculations. Round your final answer to the nearest degree.

Step-by-step explanation:

10 degrees do law of cosine stuff

Step-by-step explanation:

1. supplementary angles

2. acd and bcd

step-by-step explanation:

answer:   the paragraph proof is mentioned below.

step-by-step explanation:

given: in a δxwy where

such that, ∠wzx ≅ ∠yzx and zw≅zy

we have to prove that: segment zx is a perpendicular bisector of segment wy.

prove: since, zw≅zy ⇒ ∠wzy is a supplementary angle.

then, ∠wzy= 180°

⇒∠wzx + ∠yzx = 180° ( because xz divides ∠wzy into two parts)

but, ∠wzx ≅ ∠yzx ( given)

⇒∠wzy+∠wzy=180° ( by substitution)

⇒2∠wzy=180°

⇒∠wzy=90°

⇒∠wzy=∠yzx =90°

therefore, xz⊥wy where wz=zy

⇒zx is a perpendicular bisector of wy.