Remember that the exponent in a quadratic is never higher than 2 (because it would then no longer be the square of an unknown but a cube or something else). An equation that includes the variable x3 or x4 is not a quadratic.
Also remember to include the plus/minus sign, which indicates that the answer is a positive or negative number. Take the following simple quadratic equation:
Solve 3x2 + 4 = 31.
- First, isolate the variable by subtracting 4 from each side.
The result is 3x2 = 27.
- Next, get rid of the 3 by dividing both sides of the equation by 3.
The result is x2 = 9.
- You can now solve by using the square root rule.