A coordinate model and a tangent

A graphing exercise uses the parabola y=x² and asks for its tangent at the point where x=2. Students have access to the derivative rule for powers, but the teacher requires both the slope and a complete line equation. A classmate writes y=4x because the derivative at the point is four, while another chooses a line through the origin because the parabola passes through the origin elsewhere. The axes use the same numerical coordinate scale. There is no transformation or hidden parameter in this model. The point of tangency must satisfy both the parabola and the proposed tangent line. The exercise is independent foundational practice and does not claim to reproduce a particular official CSAT item.