If 2 triangles are similar, the ratio of one side of the triangle to the corresponding side of the other is always same for all 3 sides.
We can make use of this rule to calculate the length of sides.
From the image,
3 / 15 = 6 / x
Simplify,
1 / 5 = 6 / x
Use cross method to solve this.
5 x 6 = 1 x x
X = 30
Therefore the length of x is 30ft., A.
It is B or 2. Hope this helps
Train A: Speed of 60 mph. (1 mile per minute)
Train B: Speed of 90 mph. (1.5 miles per minute)
after 2 hours: (2:00)
Train A has gone 120 miles. (half-way mark)
Train B has gone 0 miles.
Hour 2:48: (2:48)
Train A has gone 168 miles.
Train B has gone 72 miles.
72 ----><---------------168
At 2:48 P.M the two will meet. 72+168=240
I hope this helps! :)