76/18 - X x 17/3 = 4/9
X x 17/3 = 76/18 - 4/9
X x 17/3 = 76/18 - 8/18
X x 17/3 = 34/9
X = 34/9 : 17/3
X = 34/9 x3/17
X = 2/3
`76/18 - X x 17/3 = 4/9`
`X x 17/3 = 76/18 - 4/9`
`X x 17/3 = 76/18 - 8/18`
`X x 17/3 = 34/9`
`X = 34/9 : 17/3`
`X = 34/9 x 3/17`
`X = 2/3`