Question

An equilateral triangle has a perimeter of 21 and a side length of 2x - 3. Solve for x

Answer 1

Answer:

In any triangle, Perimeter (P) = a + b + c, where, a, b and c are the sides  and P is the perimeter of the triangle

In case of equilateral triangle, the length of all sides are equal. Therefore,

P = a + a + a = 3a

Here, a = (2x - 3) and P = 21

or, 21 = 3 (2x - 3)

or, 7 = 2x - 3

or, 2x = 10

or, x = 5