Answer: z= - 498/7
i really hope you follow the steps and hope this helps!!
Explanation:
simplify 7* z/30 to 7z/30
8/5 = - 15 - 7z/30
add 15 on both sides
8/5 + 15 = - 7z/30
simplify 8/5 + 15 to 83/5
83/5 * 30 = - 7z
use the rule: a/b * c = ac/b
83*30/5 = - 7z
simplify 83*30 to 2490
2490/5 = - 7z
simplify 2490/5 to 498
498 = -7
divide both sides by -7
-498/7 = z
just flip to other side...
z= -498/7