Data:
A (Area) = 94 ft²
D (long diagonal ) = 18 ft
d (lenght diagonal ) = ?
The area of the diamond can be calculated using the following formula.
[tex]A = \frac{D*d}{2} [/tex]
Solving:
[tex]A = \frac{D*d}{2} [/tex]
[tex]94 = \frac{18*d}{2} [/tex]
[tex]94 = \frac{18d}{2} [/tex]
multiply cross
[tex]18d = 94*2[/tex]
[tex]18d = 188[/tex]
[tex]d = \frac{188}{18} [/tex]
[tex]\boxed{\boxed{d \approx 10.4\:ft}}\end{array}}\qquad\quad\checkmark[/tex]
