3x +7=5x-1
X=?
Solve the Question

  cosine theta equals negative square root of three over two; tangent theta equals negative square root of three over three

Step-by-step explanation:

If the angle were a 1st-quadrant angle, it would be ...

  arcsin(1/2) = π/6

and the other functions would be ...

  cos(π/6) = (√3)/2

  tan(π/6) = 1/√3 = (√3)/3

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The angle of interest is in the second quadrant, where the signs of cosine and tangent are negative. Hence, ...