what is 1.5z = 6

pretty simple: divide both sides by 3/2, which makes z=6/3/2=6x2/3=4

Correct Guest...!

$1.5z=6$

$1.5z\cdot \:10=6\cdot \:10$

$15z=60$

$\frac{15z}{15}=\frac{60}{15}$

$z=4$