plz help me im confused

A median is a line that divides another line (or two in this case) in half. So the length of the median is the average (mean) of the two given lines. In other words QR = 1/2 (32 + 4x - 16)
Since QR = x + 16 we have
x + 16 = 1/2 (4x + 16) Remove the brackets.
x + 16 = 1/2 * 4x + 1/2*16
x + 16 = 2x + 8 Subtract x from both sides.
16 = 2x - x + 8
16 = x + 8 Subtract 8 from both sides.
16 - 8 = x
8 = x

x = 8 <<<<<<< answer.
C<<<< answer.