Question

The figure below shows a square ABCD and an equilateral triangle DPC.

Jake makes the chart shown below to prove that triangle APD is congruent to triangle BPC.

Statements Justifications
In triangles APD and BPC; DP = PC Sides of equilateral triangle DPC are equal
In triangles APD and BPC; AP = PB Sides of equilateral triangle APB are equal
In triangles APD and BPC; angle ADP = angle BCP Angle ADC = angle BCD = 90° and angle ADP = angle BCP = 90° - 60° = 30°
Triangles APD and BPC are congruent SAS postulate


What is the error in Jake's proof?

He assumes that triangle DPC has all sides equal.

He assumes that triangle APB is an equilateral triangle.

He assumes that the triangles are congruent by the SAS postulate.

He assumes that angle ADC measures 90°.

Answer 1

He assumes that triangle APB is an equilateral triangle.

Explanation:

I took the test. If you're talking about the 05.09 segment one practice exam then, the answer is what I provided.

Answer 2

For the answer to the question above,
We can see that, DP = PC, AD = BC and ∠ ADP = ∠ BCP = 30° ( SAS postulate )
So the answer to the question above is the last one among the given choices which is Triangles APD and BPC are congruent SAS postulate.