You can fill up 4 tanks because 20 divided by 5 is 4
The bisector of the angle at A (call it AQ) divides the segment BC into segments BQ:QC having the ratio AB:AC. Use this fact to find x.
.. 9:15 = (2x -1):3x
.. 15(2x -1) = 9*3x . . . . . the product of the means equals the product of extremes
.. 30x -15 = 27x
.. 3x = 15
.. x = 5
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According to the value of x, the bisector AQ divides the triangle into two isosceles triangles: ABQ, ACQ.
It would be 10 bc ten is the next number i guess
15+3x-4+6x= 9x+11 add 6+3 then subtract 15-4
3y-4x+8x-y= 4x+2y add -4+8 then subtract 3-1
5x+8x+10x-3x= 20x Add 10+5+8 to get 23 then subtract 3