Answer:

Step-by-step explanation:
Since we're looking at perpendicular lines, the slope of the new line is the reciprocal of the original line.
So the slope of our new line is 
So far, we are looking at 
Now we need to find the b value by plugging in the given point.

So the final equation is 
Answer:
tan²x + 1 = sec²x is identity
Step-by-step explanation:
* Lets explain how to find this identity
∵ sin²x + cos²x = 1 ⇒ identity
- Divide both sides by cos²x
∵ sin x ÷ cos x = tan x
∴ sin²x ÷ cos²x = tan²x
- Lets find the second term
∵ cos²x ÷ cos²x = 1
- Remember that the inverse of cos x is sec x
∵ sec x = 1/cos x
∴ sec²x = 1/cos²x
- Lets write the equation
∴ tan²x + 1 = 1/cos²x
∵ 1/cos²x = sec²x
∴ than²x + 1 = sec²x
- So we use the first identity sin²x + cos²x = 1 to prove that
tan²x + 1 = sec²x
∴ tan²x + 1 = sec²x is identity
Answer:
540°.
Step-by-step explanation:
On a unit circle, cos θ = -1 at 180°.
However, cos θ has a period of 2π, or 360°. This means that cos θ will equal to -1 again after 2π.
To solve for the angle:
180° + 360° = 540°. This is the next angle at which cos θ = -1.