`x xx 12=456 xx 16`
`x xx 12=7296`
`x=7296:12`
`x=608`
`-------`
`x : (23xx6)=9`
`x :138=9`
`x=9 xx 138`
`x=1242`
a)
`X xx 12 = 456 xx 16`
` X xx 12 = 7296`
`X = 7296:12`
`X=608`
b)
`x:(23xx6)=9`
`x:138=9`
`x=9xx138`
`x=1242`
\(x\times12=456\times16\)
\(x\times12=7296\)
\(x=7296:12\)
\(x=608\)
______________________________
\(x:\left(23\times6\right)=9\)
\(x:138=9\)
\(x=138\times9\)
\(x=1242\)
\(x.12=456.16\\ x.12=7296\\ x=7296:12\\ x=608\)
____________________________
\(x:\left(23.6\right)=9\\ x:138=9\\ x=9.138\\ x=1242\)
X x 12 = 456 x 16 X : ( 23 x 6 ) = 9
X x 12 = 7296 X : 138 = 9
X = 7296 : 12 X = 9 x 138
X = 608 X = 1242