When using the Pythagorean theorem with a triangle, how do you know which numbers, and x, go where in the theorem?
For example, if I have a right trianle with the sides of $150$, $170$ and $x$, where $170$ is the hypotenuse, how do I know where to put the numbers in the theorem? Is it $150^2 + 170^2 = x^2$ or $150^2 + x^2 = 170^2$ or $170^2 + x^2 = 150^2$?
The theorem says $$\text{(one leg)}^2+\text{(another leg)}^2 = \text{(hypotenuse)}^2$$ In which order you put the two legs does not matter; the result of addition does not depend on the order of terms. But you need to pay attention to which side is the hypotenuse.