The question is asking "Which of these equations could equal a perfect square?"
If you're familiar with number properties regarding perfect squares, you should be able to rule out everything except the correct answer.
the fact that 5^2 - 4^2 is equal to 3^2 should be a pattern that you have memorized (esp. with regards to right triangles)
also, another one you might see often is some form of 13^2-5^2=12^2
If you're familiar with number properties regarding perfect squares, you should be able to rule out everything except the correct answer.
the fact that 5^2 - 4^2 is equal to 3^2 should be a pattern that you have memorized (esp. with regards to right triangles)
also, another one you might see often is some form of 13^2-5^2=12^2