The answer you need is -2
The expression -> 4 • 2 - 3
the answer to the expression would be 5
ΔACD is similar to ΔBCD by AA similarity theorem
AD/AC = BD/BC
x/5 = 4.2/6
6x = 21
x = 3.5
Hope this helps! ;)
B would be the correct answer. If you take 4:13 in order to form a ratio equal to that you have to multiply both sides of the ratio by the same number. 4*4=16 and 13*4=52