Solve quadratic equations

Solve the following equations:
(i) 3 - 4x² = -85 
(ii) -5x² = -500

3 - 4x² = -85
-4x² = -88   {subtracted 3 from both sides}
x² = 22   {divided both sides by -4}
x = ±√22   {took square root of both sides} 

-5x² = -500 
x² = 100   {divided both sides by -5}
x = ±10   {took square root of both sides}

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