Https://youtu.be/dQw4w9WgXcQ that helps too
Answer: 
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Explanation:
Use the pythagorean trig identity
and plug in the fact that 
Isolating sine leads to
. I'm skipping the steps here, but let me know if you need to see them.
The result is negative because we're in quadrant 4, when y < 0 so it's when sine is negative.
Therefore,

The angles that form similarity are those that are vertically opposite and 2 pairs that are equal because the for a Z formation.
Since <LPM = <ONM then
Cross multiply
12*(5x - 10) = 16*(4x - 9) Remove the brackets on both sides.
60x - 120 = 64x - 144 Subtract 60x from both sides.
- 120 = 64x - 60x - 144
-120 = 4x - 144 Add 144 to both sides.
-120 + 144 = 4x
24 = 4x Divide by 4
24/4 = x
x = 6
Answer:
3
Step-by-step explanation:
Calculate the distance using the distance formula
d = 
with (x₁, y₁ ) = (- 9, 8) and (x₂, y₂ ) = (- 3, - 1)
d = 
= 
= 
= 
= 
= 
=
× 
= 3