1. You know the perimeter is 24, and based on the measurements given, the triangles are in a 4:3 ratio, which means that all sides are also in a 4:3 ratio. Since perimeter is the sum of the lengths of all sides, the perimeter is also in a 4:3 ratio, and the answer is [spoiler]24*(4/3)=32[/spoiler]
2. You should use the pythagorean theorem to figure it out. The two legs of the triangle are 10 and 24.
10^2+24^2 = C^2 --> C = [spoiler]sqrt(100+576) = 26[/spoiler]
If you know some of the pythagorean triples, you may be able to skip the calculations. Most students should know [3,4,5], but another useful one is [5,12,13]. If you notice, the measurements in question #2 are exactly twice that.
3. Again use the pythagorean theorem to figure out the third side: B = [spoiler]sqrt(C^2-A^2) = 15[/spoiler].
Then find the area of the triangle: [spoiler]8*15/2 = 60[/spoiler]
