The formula is
YC x YD = AY x YB
fill in what we know:
18 x 6 = 9 x YB
108 = 9 x YB
YB = 108 / 9
YB = 12
A fraction x/y is a ratio between two numbers x and y.
The ratio is preserved if both x and y are scaled up or down by the same number n.
This means you can obtain any fraction equivalent to x/y by multiplying both x and y by n, i.e. (n*x)/(n*y).
Then we have 1/4 = (2*1)/(2*4) = 2/8, for example.
I think you have to count 85 and go down like 85 86 87so the answer is 15
174/29 = 6 times the difference
17*6 = 102
12*6= 72
34*6 =204
15*6 = 90
so the answer is A
Okay we know that tangent-chords creat 90 degree angles so what we have is a right triangle with a base of 9 and a height of 12, so do Pythoagoreas Theorem and we have 81+144=225 square root of 225 is 15 and that is AJ
