Answer: Yes it is a right angled triangle
Step-by-step explanation: The triangle has three sides given already which are, 8.5 cm, 6.8 cm and 5.1 cm.
In order for the triangle to qualify as a right angled triangle, the longest side must be an hypotenuse. The square of an hypotenuse must be equal to the square of the other two sides added together. This is the Pythagoras theorem, which states that
AC² = AB² + BC²
Where AC is the hypotenuse (longest side)
The longest side in this question is 8.5 cm, therefore, applying the Pythagoras theorem we now have the following expression;
8.5² = 6.8² + 5.1²
72.25 = 46.24 + 26.01
72.25 = 72.25
So, having all three sides fitted into the Pythagoras theorem, we can now conclude that the card is a right angled triangle