1/u = 1/f -1/v
1/v = 1/u + 1/f
23-8= 15 degrees it increased by 15 degrees
Answer: 
<u>Step-by-step explanation:</u>
It is given that θ is between 270° and 360°, which means that θ is located in Quadrant IV ⇒ (x > 0, y < 0). Furthermore, the half-angle will be between 135° and 180°, which means the half-angle is in Quadrant II ⇒
It is given that sin θ =
⇒ y = -7 & hyp = 25
Use Pythagorean Theorem to find "x":
x² + y² = hyp²
x² + (-7)² = 25²
x² + 49 = 625
x² = 576
x = 24
Use the "x" and "hyp" values to find cos θ:
Lastly, input cos θ into the half angle formula:

Reminder: We previously determined that the half-angle will be negative.
I got the same answer as you. Try to ask your teacher about it since it’s a math problem online or something.
Answer:
graph 1= 3. graph 2= -3
Step-by-step explanation:
the y-intercept is where it cuts the line
therefore,
graph 1=3
graph 2=-3