The answers are the one on the top right, bottom one(middle), and I think the one on the top left.
Answer:
Given: An Angle in the figure is right angle. Its measure = 90°
So,
∠2 = 90° ( vertically opposite angles are equal )
∠1 + ∠2 = 180° ( Linear Pair )
∠1 = 180 - 90
∠1 = 90°
So, ∠1 and ∠2 are
Right angles because measure of both angles are 90°.
Adjacent angles because both a common arm and a common vertex.
Supplementary angles because sum of both angles is 180°.
Step-by-step explanation:
Answer: see proof below
<u>Step-by-step explanation:</u>
Given: cos 330 = 
Use the Double-Angle Identity: cos 2A = 2 cos² A - 1

Proof LHS → RHS:
LHS cos 165
Double-Angle: cos (2 · 165) = 2 cos² 165 - 1
⇒ cos 330 = 2 cos² 165 - 1
⇒ 2 cos² 165 = cos 330 + 1
Given: 

Divide by 2: 

Square root: 
Scratchwork: 

Since cos 165 is in the 2nd Quadrant, the sign is NEGATIVE

LHS = RHS 
Answer:
36 degrees
Step-by-step explanation:
An exterior angle of a regular decagon has a measure of 36 degrees. We know this because the total measure of all the angles is 360 and a decagon has 10 sides, so each angle is 360/10 which is 36
Two consecutive negative integers are n and n+1. We are told that the product of these two integers is 600 so:
n(n+1)=600
n^2+n=600
n^2+n-600=0
n^2+25n-24n-600=0
n(n+25)-24(n+25)=0
(n-24)(n+25)=0, since we are told that n is negative...
n=-25
(...-25(-24)=600 so -25 is the value of the lesser integer)