Solve 2x^2-9 - ScanMath

Evaluate

2 x^{2} - 9

To find the roots of the expression,set the expression equal to 0

2 x^{2} - 9 = 0

Move the constant to the right-hand side and change its sign

2 x^{2} = 0 + 9

Removing 0 doesn't change the value,so remove it from the expression

2 x^{2} = 9

Divide both sides

\frac{2 x ^{2}}{2} = \frac{9}{2}

Divide the numbers

x^{2} = \frac{9}{2}

Take the root of both sides of the equation and remember to use both positive and negative roots

x = \pm \frac{9}{2}

Simplify the expression

More Steps

x = \pm \frac{3 2}{2}

Separate the equation into 2 possible cases

x = \frac{3 2}{2} x = - \frac{3 2}{2}

Solution

x_{1} = - \frac{3 2}{2}, x_{2} = \frac{3 2}{2}

Alternative Form

x_{1} \approx - 2.12132, x_{2} \approx 2.12132

Find the roots