Solve 20=0+4.905*x^2

$$20=0+4.905 \times { x }^{ 2 }$$

Solve for x

$$x = \frac{20 \sqrt{1090}}{327} \approx 2.019275109$$

$$x = -\frac{20 \sqrt{1090}}{327} \approx -2.019275109$$

Steps by Finding Square Root

Anything plus zero gives itself.

$$20=4.905x^{2}$$

Swap sides so that all variable terms are on the left hand side.

$$4.905x^{2}=20$$

Divide both sides by 4.905.

$$x^{2}=\frac{20}{4.905}$$

Expand \frac{20}{4.905} by multiplying both numerator and the denominator by 1000.

$$x^{2}=\frac{20000}{4905}$$

Reduce the fraction \frac{20000}{4905} to lowest terms by extracting and canceling out 5.

$$x^{2}=\frac{4000}{981}$$

Take the square root of both sides of the equation.

$$x=\frac{20\sqrt{1090}}{327} x=-\frac{20\sqrt{1090}}{327}$$

Steps Using the Quadratic Formula

Anything plus zero gives itself.

$$20=4.905x^{2}$$

Swap sides so that all variable terms are on the left hand side.

$$4.905x^{2}=20$$

Subtract 20 from both sides.

$$4.905x^{2}-20=0$$

This equation is in standard form: ax^{2}+bx+c=0. Substitute 4.905 for a, 0 for b, and -20 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.

$$x=\frac{0±\sqrt{0^{2}-4\times 4.905\left(-20\right)}}{2\times 4.905}$$

Square 0.

$$x=\frac{0±\sqrt{-4\times 4.905\left(-20\right)}}{2\times 4.905}$$

Multiply -4 times 4.905.

$$x=\frac{0±\sqrt{-19.62\left(-20\right)}}{2\times 4.905}$$

Multiply -19.62 times -20.

$$x=\frac{0±\sqrt{392.4}}{2\times 4.905}$$

Take the square root of 392.4.

$$x=\frac{0±\frac{3\sqrt{1090}}{5}}{2\times 4.905}$$

Multiply 2 times 4.905.

$$x=\frac{0±\frac{3\sqrt{1090}}{5}}{9.81}$$

Now solve the equation x=\frac{0±\frac{3\sqrt{1090}}{5}}{9.81} when ± is plus.

$$x=\frac{20\sqrt{1090}}{327}$$

Now solve the equation x=\frac{0±\frac{3\sqrt{1090}}{5}}{9.81} when ± is minus.

$$x=-\frac{20\sqrt{1090}}{327}$$

The equation is now solved.

$$x=\frac{20\sqrt{1090}}{327} x=-\frac{20\sqrt{1090}}{327}$$