Let F(x, y, z) = x2 + y2 + z2 - 1. For what t does F(p + d ) - 0? (Hint: Substitute Pr + tdy, Py + tdy, P: + td, for x, y, z and then factor the polynomial with respect to t. What are a, b, and in the resulting polynomial, at- + b + c) Enter your answer here What is the quadratic formula? Enter your answer here Save