Answer:
see explanation
Step-by-step explanation:
(3)
Given cosΘ = - 
Then by Pythagoras' theorem the third side is 3 ( 3,4, 5 triangle )
Since Θ in second quadrant then sinΘ > 0
sinΘ = 
Using the trigonometric identity
sin2Θ = 2sinΘcosΘ, then
sin2Θ = 2 ×
× -
= - 
(4)
Using the trigonometric identity
cos(x - y) = cosxcosy + sinxsiny
note cos15° = cos(45 - 30)°
cos(45 - 30) = cos45cos30 + sin45sin30
= (
×
) + (
×
)
= 
M = -2
In perpendicular lines, the slopes are opposite reciprocal. This means you flip the sign (from + to - or from - to +) and flip the numerator and denominator.
So 1/2 becomes negative, and 2/1 = 2
So the slope is -2
Answer:
Step-by-step explanation:
...
Yup! We're all pretty good here.