Start by getting all terms with x on one side and all terms without on the other.
6x+7=8x-15
subtract 6x from both sides
7=2x-15
add 15 to both sides
22=2x
divide both sides by 2
11=x
To solve, isolate the x. Cross multiply
3/13(13)(5) = x/5(5)(13)
3(5) = (13)x
Simplify
13x = 15
Isolate the x. Divide by 13.
13x/13 = 15/13
x = 15/13
x = 1.2
1.2 is your answer
hope this helps
tan2x*cotx - 3 = 0
We know that: tan2x = sin2x/cos2x and cotx = cosx/sinx
==> sin2x/cos2x *cosx/sinx = 3
Now we know that sin2x = 2sinx*cosx
==> 2sinxcosx/cos2x * cosx/sinx = 3
Reduce sinx:
==> 2cos^2 x/ cos2x = 3
Now we know that cos2x = 2cos^2 x-1
==> 2cos^2 x/(2cos^2 x -1) = 3
==> 2cos^2 x = 3(2cos^2 x -1)
==> 2cos^2 x = 6cos^2 x - 3
==> -4cos^2 x= -3
==> 4cos^2 x = 3
==> cos^2 x = 3/4
==> cosx = +-sqrt3/ 2
<span>==> x = pi/6, 5pi/6, 7pi/6, and 11pi/6</span>
If everything on inside of a line is 180->
(Line) --------/---------- everything on top equals 180 and there should be a number on either side. For instance 180-50 for the top would be 130, the wide angle's angle. I answer everything I like and come across so sorry I am four weeks late.
