If one triangle can be mapped to another triangle by a series of rigid transformations, then the triangles are called and the corresponding and angles are congruent.

solve systems of equations by graphing. a system of linear equations contains two or more equations e.g. y=0.5x+2 and y=x-2. the solution of such a system is the ordered pair that is a solution to both equations. to solve a system of linear equations graphically we graph both equations in the same coordinate system