Can someone help me find x?

Refer to the figure below.

According to intersecting chords theorem:
AS • SC = BS • SD
8 (x - 3) = 4 (x + 5)
8x - 24 = 4x + 20
4x = 44
x = 11

One below the 8 and another below the 4. There is also a big x made of the lines going through the circle.

x-3 / x + 5 =  1/2
2x - 6 = x + 5
x = 11

There are two inside the circle.

1 is below the No. 8 & 1 is below the No. 4.

Use the Intersecting Chords Theorem:

➤ Intersecting chords theorem: 
 — — states that the products of the lengths of the line segments on each chord are equal. 

∴

8 ( x - 3 ) = 4 ( x + 5 ) 
8x - 24 = 4x + 20
8x - 4x = 20 + 24
4x = 44
x = 11
━━━

Rectangular property of the intersecting chords says -

" When two chords intersect each other inside a circle, the products of their segments are equal."

Hence  4 * ( x + 5 )  =  8 * ( x - 3 )

=> 4 x + 20  =  8 x - 24

=> - 8 x + 4 x  =  - 24 - 20

=> - 4 x  =  - 44

=>  x  =  11  .............................. Answer

If two chords intersect inside a circle, 
then the product of the lengths of the segments of one chord 
equals the product of the lengths of the segments of the other chord. N ⋅ M = L ⋅ M.
8(x - 3) = 4(x + 5)
x = 11

It's hiding under the bed.

There are two x's, both next to an arithmetic operator and an integer.

Error: the asker must point out if the figure is
a circle.
Assume the given figure is a circle. Let
the chord containing "8 & x+3" be AB; the chord
containing " 4 & x+5" be CD. They intersect at O. Join AD & CB, then there are 2 similar triangles Tri. AOD & BOC. Thus,
AO/CO=DO/BO
=>
8/(x+5)=4/(x-3)
=>
2x-6=x+5
=>
x=11

8(x - 3) = 4(x + 5)
8x - 4x = 20 + 24
4x = 44
x = 11

4(x + 5) = 8(x - 3)

Take it from here. 

If I do that then all you'll learn is that I know how to do it.

8 +4 + x + 5 +x -3= 360 degrees

10 + 2x = 360

2x= 360 -10

2x =35

 x= 17.5 degrees

If you look closely, you'll find it inside of the circle.

the solution will be 4 * (x+5)= 8 * (x-3) it gives x =11

Note that both chords* are inside a circle, this permits we to use the

Interesecting  Chords Theorem:
 "the products of the lengths of the line segments on each chord are equals"  
So we have: 4.(x + 5) = 8 (x-3)

Expanding:

4x + 20 = 8x -24

Isolate x:
-4x = -44

x = 11


* Chord: segment that joins two points of a circle.

4x+20=8x-24
-4x=-24-20
4x=44>>x=11