Question

What is the answer to this please help!

Answer 1

$z+(-0.72)=-2.5\\\\\text{Step 1}:\ x+(-0.72)+(-0.72)=-2.5+(-0.72)\qquad\text{ERROR}\\\\CORRECT\ IS:\ x+(-0.72)-(-0.72)=-2.5-(-0.72)\\\\\text{Step 2}:\ x=-2.5+0.72\\\\\text{Step 3}:\ x=-1.78$

Subtract, not add, -0.72 from both sides.