Well, if he sold 17 of them for $18, 17 times 18 = $306. Now he has 31 backpacks left. 31 times 25 = $775. 775 + 306= $1081 (final answer) Hope it helps!!!
No, because a scalene triangle has to have all sides that are different lengths. 2 sides being 13 inches would mean that the triangle has 2 sides that are equal, making it an isosceles triangle.