Solve the Equation Using the Quadratic Formula (When Necessary, Round $- 5 z ^ { 2 } - 6 = - 7 z ^ { 2 }$

Short Answer

Solve the equation using the quadratic formula (when necessary, round results to three significant digits). $- 5 z ^ { 2 } - 6 = - 7 z ^ { 2 }$