Respuesta :

Answer: [tex]x=\±2\sqrt{10}[/tex]

Step-by-step explanation:

To find the solutions of the quadratic equation given in the problem, you can apply the proccedure shown below:

- Subtract 40 from both sides of the equation.

- Multiply both sides of the equation by -1

- Apply square root to both sides of the equation.

Therefore, by applyin the steps above, you obtain:

[tex]40-x^2-40=0-40\\-x^2=-40\\(-1)(-x^2)=(-40)(-1)\\\\x^2=40\\\\\sqrt{x^2}=\±\sqrt{40}\\\\x=\±2\sqrt{10}[/tex]

Answer:

= ±2√10

Step-by-step explanation:

40 − x2 = 0

We could solve this by;

subtracting x² from both sides

we get;

40 = x²

Then we get the square root on both sides;

√x² = √40 ; but the square root of a positive number "a" is +√a or -√a

Therefore;

√x² = ± √40

x = ±√40

√40 = √4√10

       = 2√10

Thus;

x = ±2√10