Answer: The cost of 97.5 square feet of glass is $1828.13
( Incredible! Who has a window that size in their house?!?! )
Explanation:
The Area (not perimeter) is 1/2 b*h
To find the height if this equilateral triangle we can use the Pythagorean Theorem c² = a² + b²
The side of the triangle is 15; that is the hypotenuse, c
The base of the right triangle we need is 7.5
The altitude (height) is what we need to calculate.
15² = a² + 7.5²
225 = a² + 56.25 Subtract 56.25 from both sides, then take the square root to find a, that is h in the Area equation.
√168.25 = 12.99 . Round to 13
Calculate the Area = 1/2 b*h
15*13/2 = 97.5 square feet.
Multiply by the cost per square foot: $18.75
97.5 * 18.75 = 1828.125 . Round to $1828.13