Answer
$a\geq\frac{1}{2}$
Work Step by Step
$4(a-2)-6a\leq-9\longrightarrow$ multiply using the distributive property
$4a-8-6a\leq-9\longrightarrow$ combine like terms
$-2a-8\leq-9\longrightarrow$ add 8 to each side
$-2a-8+8\leq-9+8\longrightarrow$ add
$-2a\leq-1\longrightarrow$ divide both sides by -2; reverse the inequality sign
$-2a\div-2\geq-1\div-2\longrightarrow$ divide
$a\geq\frac{1}{2}$
