Answer:
89.4 inches
Step-by-step explanation:
The slant height of the square pyramid, the height of the square pyramid and half the base side of the square pyramid altogether form a right triangle.
In this right triangle, the slant height is the hypotenuse.
By the Pythagorean theorem,
[tex]91.5^2=19.4^2+h^2\\ \\h^2=91.5^2-19.4^2\\ \\h^2=8,372.25-376.36\\ \\h^2=7,995.89\\ \\h=\sqrt{7,995.89}\ in\\ \\h\approx 89.4\ in[/tex]
