Final answer:
True - Pythagorean theorem can be used to calculate the length of a resultant vector from two vectors at right angles.
Step-by-step explanation:
The statement True - We can use the Pythagorean theorem to calculate the length of the resultant vector obtained from the addition of two vectors which are at right angles to each other.
The Pythagorean theorem states that in a right triangle, the square of the hypotenuse (the side opposite the right angle) is equal to the sum of the squares of the other two sides.
When two vectors are at right angles to each other, they form a right triangle, and we can use the Pythagorean theorem to calculate the length of the resultant vector.