Based on the information marked in the diagram, two triangles must be congruent.

Check the final answer first, then review the worked steps.

Problem

Based on the information marked in the diagram, two triangles must be congruent.

Answer

False

Step-by-step solution

1. Analyze the given information for triangle XYZ:
We are given that $\angle XZY$ is a right angle (indicated by the square symbol), so $\angle XZY = 90^\circ$. The tick marks on sides $XZ$ and $YZ$ indicate that $XZ = YZ$. This means triangle XYZ is an isosceles right triangle.

2. Analyze the given information for triangle ABC:
We are given that $\angle ACB$ is a right angle (indicated by the square symbol), so $\angle ACB = 90^\circ$. The double tick marks on sides $BC$ and $AB$ indicate that $BC = AB$. This means triangle ABC is an isosceles triangle, but it is not necessarily a right triangle at C. However, the diagram shows a right angle at C, implying $\angle ACB = 90^\circ$. The double tick marks on $BC$ and $AB$ are contradictory if $\angle ACB = 90^\circ$, as the hypotenuse ($AB$) must be longer than the legs ($BC$ and $AC$). Assuming the tick marks on $BC$ and $AC$ were intended to be equal, then $\triangle ABC$ would be an isosceles right triangle with $BC = AC$. If we strictly follow the diagram, the double tick marks on $BC$ and $AB$ imply $BC = AB$. In a right triangle, the hypotenuse is always the longest side, so $AB > BC$. Therefore, $BC = AB$ is only possible if $BC = AB = 0$, which is not a triangle. Let's assume there is a typo in the tick marks for $\triangle ABC$ and that the intention was to show $BC = AC$ to make it an isosceles right triangle, or that the double tick marks on $BC$ and $AB$ are correct and it is not an isosceles right triangle.

3. Compare the triangles for congruence:
For $\triangle XYZ$ to be congruent to $\triangle ABC$, we need to satisfy one of the congruence postulates (SSS, SAS, ASA, AAS, or HL for right triangles).

From $\triangle XYZ$, we have: $\angle XZY = 90^\circ$, $XZ = YZ$.

From $\triangle ABC$, we have: $\angle ACB = 90^\circ$, and $BC = AB$ (as marked, though this is geometrically impossible for a non-degenerate triangle).

Let's consider the case where the tick marks on $BC$ and $AC$ were intended to be equal, so $BC = AC$. In this case, $\triangle ABC$ is an isosceles right triangle with $\angle ACB = 90^\circ$ and $BC = AC$. We also have $XZ = YZ$ in $\triangle XYZ$. However, we do not have any information about the angles in $\triangle ABC$ or $\triangle XYZ$ other than the right angles, nor do we have information about the lengths of the hypotenuses ($XY$ and $AB$) or the other legs ($YZ$ and $AC$).

Even if we assume $\triangle ABC$ is an isosceles right triangle with $BC=AC$, we only know that $XZ=YZ$ and $BC=AC$. We do not know if $XZ = BC$ or $YZ = AC$. Therefore, we cannot conclude congruence.

If we strictly follow the diagram with $BC = AB$, this is an impossible triangle. However, if we interpret the double tick marks on $BC$ and $AB$ as a mistake and assume that the diagram intends to show some relationship, we still lack sufficient information.

Let's assume the question implies that $\triangle XYZ$ is an isosceles right triangle (which it is, based on $XZ=YZ$ and $\angle XZY = 90^\circ$) and $\triangle ABC$ is also an isosceles right triangle (which it would be if $BC=AC$ and $\angle ACB = 90^\circ$). Even in this scenario, we only have Angle-Leg-Leg (ALL) congruence, which is not a valid congruence postulate. We would need at least one more piece of information, such as $XZ = AC$ or $YZ = BC$ or $XY = AB$ or $\angle YXZ = \angle BAC$.

Given the markings, we have: $\angle XZY = 90^\circ$, $XZ = YZ$. And $\angle ACB = 90^\circ$, $BC = AB$. The condition $BC=AB$ in a right triangle is impossible. If we ignore this and assume it's a typo and meant $BC=AC$, then we have two isosceles right triangles. However, we do not have enough information to prove congruence. For example, $\triangle XYZ$ could be smaller than $\triangle ABC$.

Therefore, based on the information marked in the diagram, $\triangle XYZ$ and $\triangle ABC$ do not necessarily have to be congruent.