Question

doblan un alambre primero en forma rectangular con 9 in de ancho y 12 in de longitud. si cada lado del triángulo tiene la misma longitud, ¿cuál es esta longitud?

Explanation:

Step1: Calculate perimeter of rectangle

The perimeter formula of a rectangle is $P = 2(l + w)$. Given $l = 12$ in and $w = 9$ in, then $P=2(12 + 9)=2\times21 = 42$ in.

Step2: Find side - length of equilateral triangle

Since the wire is reshaped into an equilateral triangle and the length of the wire (perimeter) remains the same. The perimeter of an equilateral triangle is $P = 3s$, where $s$ is the side - length. We know $P = 42$ in, so $s=\frac{42}{3}=14$ in.

Answer:

14