Cot(theta -pi/2) = cos(theta - pi/2)/sin(theta - pi/2)
using cosine and sin law
= [cos(theta)*cos(pi/2)+sin(theta)*sin(pi/2)] / [sin(theta)*cos(pi/2) - cos(theta) * sin(pi/2)]
by simplify it :
= sin(theta) / -cos(theta)
= -tan(theta)
Answer:
Ben is 20 years old.
Step-by-step explanation:
Ben: x + 5
Kelsey: x
x + 5 + x = 3x - 10
2x + 5 = 3x - 10
-1x = -15
x = 15
Kelsey is 15 years old, Ben is 20 years old.
Answer:
y = -2x + 9
Step-by-step explanation:
The slope of the line can be found from 2 points.
(y2-y1)/(x2-x1)
7-3/1-3
4/-2
= -2
-2 is the slope.
The y-intercept is 9.
The equation of a line is y=mx+b.
m is the slope, and b is the y-intercept.
y = -2x + 9