Answer:
The lengths 14, 24, and 26 cannot be the sides of a right triangle. The lengths 30, 72, 78 can be the sides of a right triangle.
Step-by-step explanation:
To prove that the lengths 14, 24, and 26 cannot be the sides of a right triangle:
a=14, b=24, c=26
Pythagoreon theorem: a^2+b^2=c^2
substitute values in: 14^2+24^2=26^2
simplify: 196+576=676
simplify again: 772=676, which is not true
This proves that the lengths 14, 24, and 26 cannot be the sides of a right triangle.
To prove that the lengths 30, 72, and 78 can be the sides of a right triangle:
a=30, b=72, c=78
Pythagoreon theorem: a^2+b^2=c^2
substitute values in: 30^2+72^2=78^2
simplify: 900+5184=6084
simplify again: 6084=6084, which is true
This proves that the lengths 30, 72, and 78 can be the sides of a right triangle.