Solve 5*A*A=245

$$5 \times A \times A = 245$$

Solve for A

$$A=7$$

$$A=-7$$

Steps by Finding Square Root

Multiply A and A to get A^{2}.

$$5A^{2}=245$$

Divide both sides by 5.

$$A^{2}=\frac{245}{5}$$

Divide 245 by 5 to get 49.

$$A^{2}=49$$

Take the square root of both sides of the equation.

$$A=7 A=-7$$

Steps Using the Quadratic Formula

Multiply A and A to get A^{2}.

$$5A^{2}=245$$

Subtract 245 from both sides.

$$5A^{2}-245=0$$

This equation is in standard form: ax^{2}+bx+c=0. Substitute 5 for a, 0 for b, and -245 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.

$$A=\frac{0±\sqrt{0^{2}-4\times 5\left(-245\right)}}{2\times 5}$$

Square 0.

$$A=\frac{0±\sqrt{-4\times 5\left(-245\right)}}{2\times 5}$$

Multiply -4 times 5.

$$A=\frac{0±\sqrt{-20\left(-245\right)}}{2\times 5}$$

Multiply -20 times -245.

$$A=\frac{0±\sqrt{4900}}{2\times 5}$$

Take the square root of 4900.

$$A=\frac{0±70}{2\times 5}$$

Multiply 2 times 5.

$$A=\frac{0±70}{10}$$

Now solve the equation A=\frac{0±70}{10} when ± is plus. Divide 70 by 10.

$$A=7$$

Now solve the equation A=\frac{0±70}{10} when ± is minus. Divide -70 by 10.

$$A=-7$$

The equation is now solved.

$$A=7 A=-7$$