1. Let's consider the problem about triangles. Since no specific problem is given, we'll review the general properties of triangles and how to find the area. 2. A triangle is a polygon with 3 edges and 3 vertices. 3. The sum of the internal angles of a triangle is always $180^\circ$. 4. The area $A$ of a triangle with base $b$ and height $h$ is given by the formula: $$ A = \frac{1}{2} b h $$ 5. If you have the lengths of all sides $a$, $b$, and $c$, you can use Heron's formula to find the area: First calculate the semi-perimeter: $$ s = \frac{a + b + c}{2} $$ Then the area is: $$ A = \sqrt{s(s - a)(s - b)(s - c)} $$ 6. For right triangles, where one angle is $90^\circ$, you can use the legs as base and height. If you have a specific triangle problem, please provide the details so I can help solve it step by step.