1. Nine points are arranged in a 3 x 3 grid, as shown below. In how many different ways can you choose three points, so that they form a triangle?
2. A right isosceles triangle has a hypotenuse of 1. What is the area of the triangle?
1. How many ways can you choose 3 points - how many ways can you choose 3 points that form a line?
2. If you connect two right isosceles triangle with a hypotenuse of 1 by the hypotenuse, you get a sqaure. Find the area of the square/2.