To answer this question you need to understand the relationship between the hypotenuse and the 2 other sides of a right triangle. We use The pythagorean theorem to help us see the relationship. 3^2+4^2=c^2, so 25=c^2. C=5.
You will use the lines to show 3 and 4 and the hypotenuse is the slanted side. See picture.
