Can someone help me on this question? The question is down below...

12m

Step-by-step explanation:

Because you are given that this is a right angled triangle, you can apply the pythagoras theorem where a^2 = b^2 + c^2

15^2 = 9^2 + x^2

225-81 = x^2

144 = x^2

x = 12m

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

other answer is correct. i had used the radius of the radius somehow. a website: