Geometry Help Please! ASAP

https://media.glynlyon.com/a_matgeo_2011/5/groupi44.gif

Given:

AB is parallel to RS

If CR = 3, RA = 5, and CS = 4, find SB.
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https://media.glynlyon.com/a_matgeo_2011/5/groupi45.gif
Given:
Angle 1 = Angle 2

If AC:BC = 3:5 and AB = 12, find AD:_____ and DB:______
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https://media.glynlyon.com/a_matgeo_2011/5/b1.gif

In the figure below, the segment is parallel to one side of the triangle. Find the values of x and y .

x=
y=
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https://media.glynlyon.com/a_matgeo_2011/5/c2.gif

In the figure below, the segment is parallel to one side of the triangle. Find the value of x .

x=
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first question:

In order to solve this , use thales theorem:

If AB||RS

then

CS/CB = CR/CA

CA=3+5 =8

put SB=x

CB=x+4

4/x+4 = 3/8

32 = 3(x+4)

32=3x+12

20 = 3x

x=20/3

SB=20/3

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second question

In order to solve this , use the angle bisector theorem:

If in your problem angle1 =angle 2 , then:

AC:BC = AD:BD

AD:BD = 3:5 (becuase AC:BC=3:5)

put AD =x , thus BD =12-x (because AB=12)

3/5 = x/12-x

3(12-x) = 5x

36-3x=5x

36=8x

x=36/8 =9/2

which means that AD=9/2 and BD = 15/2

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third question

If the segment is parallel to one side of the triangle , then you have to use thales theorem again (explanation see above in the first answer of your first question)

y/12 = 4/16

16y= 48

y=3

and

x/x+9 = 4/16

16x= 4(x+9)

16x=4x+36

12x=36

x=3

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fourth and last question

once more=thales theorem

x/2x+7 = 16/38

38x= 16(2x+7)

38x=12x+112

26x=112

x=56/13