A right triangle has side lengths of x-1, x+1, and x+3. What is its perimeter?

If you’re *really* on your right triangles game, you might instantly think of the Pythagorean triples you know and see if any fit into that scheme (hint: one will!). If not, just put those values into the Pythagorean theorem and solve for *x*:

From there, you know *x* = 7, because the sides of the triangle aren’t going to be negative.

That means your sides are 6, 8, and 10, and your perimeter is 24.