Respuesta :

Answer: A

Step-by-step explanation:

Since we know that T is the midpoint of SU, we know that it bisects SU. Now, we know that it cuts SU in half. With that, we know that ST and TU are equal.

3x=2x+20                                            [subtract both sides by 2x]

x=20                        

Now that we know x, we can plug them in to solve for each segment.

ST

3x                                                        [plug in x=20]

3(20)                                                    [multiply]

60

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TU

2x+20                                                 [plug in x=20]

2(20)+20                                             [multiply]

40+20                                                  [add]

60

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SU

60+60=120

We know that SU is ST and TU combines, therefore, we add the values of ST and TU.