(When calculating don't forget it says 1cm=3 feet so I multiplied my numbers by 3 and then calculated the areas)The rectangle area is Base x height so 6x12=72 and the triangle area is 1/2xbasexheight so it's 6x6x1/2=18. 72+18=90 and note it says he only drew half of the side of the house so multiply 90x2=180