Question

using diagonals from a common vertex, how many triangles could be formed from the polygon pictured below?

Explanation:

Step1: Recall the formula

The number of triangles formed by drawing diagonals from a single - vertex of an $n$-sided polygon is $n - 2$.

Step2: Count the number of sides

The given polygon has 7 sides, so $n=7$.

Step3: Calculate the number of triangles

Substitute $n = 7$ into the formula $n - 2$. We get $7-2=5$.

Answer:

5