Help me to solve tan^3 2x-3tan2x+2=0

What is sin 7x/4 ? i need on this urgent trig

Astudent draws two parabolas on graph paper. both parabolas cross the x-axis at (–4, 0) and (6, 0). the y-intercept of the first parabola is (0, –12). the y-intercept of the second parabola is (0, –24). what is the positive difference between the a values for the two functions that describe the parabolas? write your answer as a decimal rounded to the nearest tenth

What is the value of x? assume that the line is tangent to the circle.