Geometry: Geometry of a Triangle

Think and Click Icon Think & Click: Congruent Triangles

Now, you try. Complete the Think & Click activity by looking at each problem below, thinking about it, and then clicking on the question to reveal the solution.

Triangle ABC is congruent to triangle XYZ.

triangle ABC with side AB labeled 7 and side BC labeled 2x plus 3.  Triangle XYZ with side YZ labeled 25 and side ZX labeled 41

Find the value of x.
 

Since side BC is congruent to side YZ, 2x + 3 = 25, x = 11.
 

If the measure of angle A equals 47 degrees, the measure of angle B equals (8y + 8)°, and the measure of angle Z equals (4y + 5)°. Find the value of y.
 

Since the triangles are congruent, angle C is congruent to angle Z.  The three angles must add up to 180.

47 + 8y + 8 + 4y + 5 = 180°

y = 10