Question

help

Answer 1

You are gonna have to use some trigonometry.
specifically, cosine, so

\[\large cos (64) = \frac{7}{x} \]

Answer 2

Multiply by x, divide by cosine:

\[\large x= \frac{7}{cos(64)} \]

Answer 3

Well, the volume of a pyramid is:

\[\large V = \frac{l*w*h}{3} \]
So just plug in the values you have

\[\large 392 = \frac{14*7*h}{3} \]
\[\large 1176 = 14*7*h \]
then just divide by 14*7, which is 98

\[\large \frac{1176}{98} = h\]