Answer:
Yes - it is a triangle
Classification: Right Triangle
Explanation:
5 + 7 = 12
√74 > 12
This is a triangle because the sum of the two lesser side lengths are greater than the longest side length.
5² + 7² =? (√74)²
25 + 49 =? 74
74 = 74
This is a right triangle because the sum of the squares of the two sides are equal to the square of the length of the hypotenuse.
(Think Pythagorean Theorem)