How to measure the angle of this Pyramid/Prism/Tent like shape?

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I was designing this model with glasses. The front triangle sides are $a, b$ and $c$. And the slant height is $h$. The top length is $l$ and bottom full length is $L$. enter image description here

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One value that is fixed is the back side triangle angle i.e. $\,45\unicode{176}\,$ (forty-five degrees).

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Now I need help to find relation between these values so I can design it for different value? Anyone can help me ?

Edited: $x=45\unicode{176}$ (forty-five degrees) which is the front triangle slanted angle. enter image description here

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From the values of $c,h,l,L$ you can obtain the values of $a,b$, the height $H$ of the solid and the lengths of the sides of the back triangle.

The height of the solid is

$H=\sqrt{h^2-(L-l)^2}\;.$

The values of $a,b$ are

$a=\sqrt{h^2+(c-H)^2}\;,$

$b=\sqrt{2h^2-(L-l)^2}\;.$

The length of the side of the back triangle which forms the $45\unicode{176}$-angle with the base is $H\sqrt2$.

The length of the base is $c$.

The lenght of the other side is $\sqrt{H^2+(c-H)^2}$.

Addendum :

If we know that $x=45\unicode{176}$ (forty-five degrees) which is the front triangle slanted angle, then we can get all the lengths from $c,l,L$ in the following way :

$H=L-l$

$h=\sqrt2\big(L-l\big)$

$a=\sqrt{2(L-l)^2+(c+l-L)^2}\;,$

$b=\sqrt3\big(L-l\big)$

The length of the side of the back triangle which forms the $45\unicode{176}$-angle with the base is $\sqrt2\big(L-l\big)$.

The length of the base is $c$.

The length of the other side is

$\sqrt{(L-l)^2+(c+l-L)^2}\;.$