# How do you solve 2z + 9.75 - 7z = -5.15?

Collect $z$ on one side and numbers on the other:
$2 z - 7 z = - 9.75 - 5.15$
$- 5 z = - 14.9$
divide both sides by $- 5$;
$z = - \frac{14.9}{-} 5 = 2.98$