Tan x = sin x / cos x , therefore tan (90-a) = ? . (all angle measurements are in degrees)
choices are below:
a. 1/tan(90-a)
b. 1/sin a
c. 1/cos(90-a)
d. 1/tan a

Option D.

Step-by-step explanation:

tan ( 90-A ) =

since  sin (90-A) = cos A

and cos (90-A) = sin A

So  

Option D. is the correct answer.

b. x- 48 =120

step-by-step explanation:

c. y = 1/4 x + 5

step-by-step explanation:

first, put the equation of the line on the graph into slope-intercept form

(y = mx + b):   y = -4x + 8

second, a perpendicular line has to have "an opposite/reciprocal slope" to the original slope. so, find the "m" value in your original equation (it's -4, right? )

original slope: m = -4   perpendicular slope: change the sign to its opposite and find the reciprocal ("flip" the number)

new slope is now positive (b/c the original slope was negative 4), and it's 1/4 (not the original slope of 4 or 4/1)