Problem3x2−12=03x^2 - 12 = 03x2−12=0Step-by-step solution兩邊同加 121212：3x2=123x^2 = 123x2=12。兩邊同除以 333：x2=4x^2 = 4x2=4。取正負平方根：x=±2x = \pm 2x=±2。Answerx=2orx=−2x = 2 \quad \text{or} \quad x = -2x=2orx=−2Want to solve a different problem? Open the quadratic solver →Related worked examples/solve/algebra/x2-minus-9/solve/algebra/x2-minus-25