Method 1 (side, side, side): Measure the sides of each triangle with a ruler. If the three measurements from each triangle are the same, the triangles are congruent.
Method 2 ( side, angle, side): Measure two of the sides that join each other with a ruler, and measure the angle where they join with a protractor. Repeat for both triangles. If the sides are the same length and the angles are the same, the triangles are congruent.
Method 3 (angle, side, angle): Measure two of the angles with a protractor. Measure the included side that runs between them with a ruler. Repeat for both triangles. If the measurements are the same, the triangles are congruent.
Method 4 (angle, angle, side): Measure two angles with the protractor, and measure any non-included side. Repeat for both triangles. If all measurements are the same, the triangles are congruent.
Method 5 applies only to right-angle triangles, which are triangles with a 90-degree angle. For each triangle, measure the hypotenuse, which is the side opposite the 90-degree angle. Then measure one of the other two legs. If the measurements are equal for both triangles, the triangles are congruent.