Answer:
25
Explanation:
For these types of problems you'll need the Pythagorean theorem (woohoo..). This amazing formula looks like: a^2 + b^2 = c^2. The a and b in this formula are the legs of the triangle, the straight non-diagonal lines. The c stands for the hypotenuse which is the diagonal line.
Since you have both of the legs we can go ahead and plug that into our equation: 15^2 + 20^2 = c^2.
NOTE: It doesn't matter which leg you plug into which variable! Just make sure it's not c!
With exponents, it just means to multiply the number by itself. 15^2 is the same as 15(15). So, simplifying the equation, we get: 225 + 400 = c^2.
This part is pretty straightforward. I mean, unless you don't remember addition... Adding it together, you will get 625 = c^2.
This part kinda requires a calculator if you don't know all of your square roots. Luckily, this is a perfect root and goes into 25.
And that, my friend, is your answer. Hope this helped :)