(a) Find the y-intercept of the line in 2-space that is represented by the vector equation r = (3+2t)i+5tj (b) Find the coordinates of the points where the line r = ti + (1+2t)j - 3tk intersects the plane 3x-y-z=2 For a, I'm pretty sure it's (0,-7.5), just took (3,0) and went in the direction v=2i+5j to the y-intercept. For b, I listed the point (0,1,0) from the coordinates of r and the vector v=i+2j-3k. After combining them with guess and check, I came up with the answer of (3/4, 10/4, -9/4). I'm pretty sure I have the right answers, but I technically ended both with guess and check. What is the proper way to finish both problems?