Construct an angle congruent to ABC using EF as one side

Find parametric equations for the line tangent to the curve of intersection of the surfaces at the given point. surfaces: xsquared2plus+2yplus+2zequals=1212 yequals=33 point: left parenthesis 1 comma 3 comma five halves right parenthesis

Find the perimeter of the triangle with vertices  d(3, 4),  e(8, 7), and  f(5, 9). do not round before calculating the perimeter. after calculating the perimeter, round your answer to the nearest tenth.  

What is the value of x? enter your answer in the box.