Answer
$y=1$
Work Step by Step
$6(6-4y)=12y$ $\longrightarrow$distributive property
$36-24y=12y$ $\longrightarrow$addition property
$36-24y+24y=12y+24y$ $\longrightarrow$simplify
$36=36y$ $\longrightarrow$multiplication property
$36\div36=36y\div36$ $\longrightarrow$simplify
$1=y$