A right triangle has a hypotenuse of 30 inches. Both of its legs are the same length. How long is a leg of this right triangle?
This problem is describing a triangle that looks like this:
We know that if we sum the squares of the legs, we find the square of the hypotenuse. We said that earlier, in that sentence you reread 37 times. Therefore,
x2 + x2 = 302
2x2 = 900.
From this point onward, it's kid's stuff. We divide each side by 2 to find x2 = 450 and see that
Since we're talking about a triangle here, we can't have a side with a negative length. As screwy as our system of measurement is compared to the metric system, at least there is no such thing as negative inches, even if a British person (hi, guys!) tries to imply that there is.
We determine that a leg of this triangle must have length .