Answer
4.97 inches
Work Step by Step
Let the side length of the triangle be s and the vertices be labeled A, B, C. Draw the height of the triangle from A to BC and let D be the point where the height intersects BC.
Since the angles in an equilateral triangle are all 60 degrees, ABD is a 30-60-90 triangle. Thus, BD = $\frac{1}{2}$s and AD = $\frac{\sqrt{3}}{2}$s. We also know that the height is 4.3 inches. So 4.3 = $\frac{\sqrt{3}}{2}$s. Multiplying both sides by $\frac{2}{\sqrt{3}}$, we have s = $4.3*\frac{2}{\sqrt{3}}$ = 4.97 inches.
