`479 - y xx 5 = 896:4 `
`479 - y xx 5 = 224`
`y xx 5 = 479 -224`
`y xx 5 = 255`
`y=255:5`
`y=51`
____________________________________
`y:9 -8399=4938-924`
`y:9 -8399=4014`
`y : 9 =4014 + 8399`
`y :9 = 12413`
`y= 12413 xx 9`
`y=111717`
________________________________
`(18490+y)+428=49202`
`18490+y = 49202 - 428`
`18490+y = 48774`
`y=48774-18490`
`y=30284`
_________________________________
`(1848-y):15=83`
`1848-y = 83 xx 15`
`1848-y =1245`
`y=1848 - 1245`
`y=603`