7(tan(a+b))=5(tan(a+b)) then find the value of sin2a/sin2b

Yvaries inversely as x. y =12 when x=5. find y when x=4

M? aoc=96 ? space, m, angle, a, o, c, equals, 96, degree \qquad m \angle boc = 8x - 67^\circm? boc=8x? 67 ? space, m, angle, b, o, c, equals, 8, x, minus, 67, degree \qquad m \angle aob = 9x - 75^\circm? aob=9x? 75 ? space, m, angle, a, o, b, equals, 9, x, minus, 75, degree find m\angle bocm? bocm, angle, b, o, c:

Is experimental probibilty the same as the observed frequency in math? i need the answer asap!