Solve 28-7x^2 - ScanMath

Evaluate

28 - 7 x^{2}

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

28 - 7 x^{2} = 0

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

- 7 x^{2} = 0 - 28

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

- 7 x^{2} = - 28

Change the signs on both sides of the equation

7 x^{2} = 28

Divide both sides

\frac{7 x ^{2}}{7} = \frac{28}{7}

Divide the numbers

x^{2} = \frac{28}{7}

Divide the numbers

More Steps

x^{2} = 4

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

x = \pm 4

Simplify the expression

More Steps

x = \pm 2

Separate the equation into 2 possible cases

x = 2 x = - 2

Solution

x_{1} = - 2, x_{2} = 2

Factor the expression