Answer:
Expanded Form. When we write the number 521, what that number really means is that we have the total of 500 + 20 + 1. We've expanded the number to show the value of each of its digits. When we expand a number to show the value of each digit, we're writing that number in expanded form.
<h3>The solution as an ordered pair is (x,y) = (2,2)</h3><h3>x = 2 and y = 2 pair up together.</h3>
===============================
Work Shown:
4x+2y = 12
4x+2( y ) = 12
4x+2( 2x-2 ) = 12 ... replace y with 2x-2
4x+2( 2x ) + 2( -2 ) = 12 ... distribution rule
4x+4x-4 = 12
8x-4 = 12
8x-4+4 = 12+4 ... add 4 to both sides
8x = 16
8x/8 = 16/8 ... divide both sides by 8
x = 2 is the first part of the answer
Use x = 2 to find y
y = 2x-2
y = 2(2)-2 ... replace x with 2
y = 4-2
y = 2 is the second part of the answer
Cot(5pi/12) = tan(pi/12)
tan(x/2) = (1 - cos(x)) / sin(x))
tan(pi/12) = tan((pi/6)/2) = (1 - cos(pi/6)) / sin(pi/6))
sin(pi/6) = 1/2
cos(pi/6) = sqrt(3) / 2
so...
tan(pi/12) = (1 - sqrt(3)/2) / (1/2) = 2 - sqrt(3)