The area of a triangle can be calculated through the equation,
A = bh / 2
where A is area, b is base, and h is height.
Substituting the known values from the given above to the equation
A = (14 in)(6 in) / 2 = 42 in²
Since, there are five of these triangles, the total area is,
total area = 5(42 in²) = 210 in²
Thus, the total area of the plywood needed is 210 in².