Weegy: The slope of 3+4x=2y-9 is 2.
User: write an equation in slope-intercept form for the line that is parallel to y=2x+6 and passes through the point (4,-4)
Weegy: There are two relevant trig identities, as well as the definition of the tangent:
tan(z) = sin(z) / cos(z)
These are the two identities. [ [ You can find them in any trig book or in Wikipedia:
(1) sin(2x) = 2*sin(x)*cos(x)
(2) cos(2x) = cos^2(x) - sin^2(x)
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First I have to compute cos(x)
When the sine is 5 / 13, that means that, by the definition of the sine:
sin(x) = (side opposite angle) / (hypotenuse)
So letting "side opposite" = 5 and "hypotenuse" = 13, and calling the length of the "side opposite" a and the length of the hypotenuse c, by the Pythagorean Theorem (where b = the length of the other side, called the adjacent side):
a^2 + b^2 = c^2..............So:
5^2 + b^2 = (13)^2
25 + b^2 = 169
b^2 = 169 - 25 = 144
b = sqrt(144) = 12.
So cos(x) = 12/13.....
User: y=-1/4x+2
Weegy: y = -1/4x + 15 and y = 4x - 17 are perpendicular.
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