When solving the area of a triangle we need to have A= hb/2
h: being the height of the triangle has and b: being the base of the triangle when joining these two number you always have divide by 2 when finding an area of a triangle giving you your final equation:
The possible outcomes for the coin is 2 out of 1 since a coin has 2 sides the coin may only land on 1 side but the chances are between both sides having a 50/50 chance to land on either side.