Answer:
B
Step-by-step explanation:
two sides are longer than the other two, D could also be one of the choices but rectangles have two parallel lines and have shorter sides at the sides
For this case we must solve the following system of equations:

To solve we follow the steps below:
We multiply the second equation by -3:

Thus, we have the equivalent system:

We add the equations:

We look for the value of the variable "y":

Thus, the solution of the system is given by:

Answer:

<h3>
Answer: 19</h3>
==============================================================
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.