Assuming T, B and N are all on the same line, then we can say
BT + TN = BN
which is the segment addition postulate.
Subtract TN from both sides to get
BT + TN = BN
BT + TN - TN = BN - TN
BT = BN - TN
BN - TN = BT
Which is what choice C is saying. Therefore the answer is choice C.
The percentage change is 6.54%
You have to divide 1800÷1926, then multiply by 100 and you'd get 93.46, then subtract 100-93.46 which equals 6.54% :)
Divide 1500 by 1000
1500/1000 = 1.5