What is the value of x?
A.) 15
B.) 22
C.) 25
D.) 20

Step-by-step explanation:

From the same external point B, the tangents AB and BC to a circle are equal.

x+15=2x-5

=>x-2x = -5-15

=>-x = -20

=>x= 20

congruent segments

step-by-step explanation:

a 4/6 = 9/12   not proportional

step-by-step explanation:

to find which are not proportional, we can use cross products

if it is true, they are proportional.   if it is not true, they are not proportional.

a 4/6 = 9/12

4* 12 = 6*9

48 = 54

not this is not proportional  

b 2/3 = 12/18  

2* 18 = 3 * 12

36 = 36

this is proportional

c 5/4 = 10/8  

5*8 = 4*10

40 = 40

this is proportional

d 7/5 = 35/25

7*25 = 5 * 35

175 = 175

is proportional