They would be similar triangles because they cannot be congruent due to the fact that the side lengths are different. They are dilutions of each other which again proves that they are similar, not congruent.
For this case we have that by definition, the line equation of the slope-intersection form is given by:

Where:
m: It's the slope
b: It is the cut-off point with the y axis
According to the statement we have:

Thus, the equation is of the form:

We substitute the given point and find "b":

Finally, the equation is of the form:

Answer:

<h3>
Answer: 19</h3>
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Explanation:
T is the midpoint of PQ, which means T splits PQ into two equal parts. Those parts being PT and TQ.
Set them equal to each other and solve for x.
PT = TQ
3x+7 = 7x-9
3x-7x = -9-7
-4x = -16
x = -16/(-4)
x = 4
So,
PT = 3x+7 = 3*4+7 = 19
TQ = 7x-9 = 7*4-9 = 19
Both PT and TQ are 19 units long to help confirm the answer.