Complex Number Definition

A complex number z is a point in the plane where the x-axis is measured in real units and the y-axis is measured in imaginary units. Notice x=Re(z) and y=Im(z). What is the locus of points that satisfy Re(z)=Im(z)? What is the locus of points that satisfy Re(z)=3? What is the locus of points that satisfy Im(z)=2?