8.

Question

Find the number of real number solutions for the equation.

x2 − 18 = 0

1

0

2

Answer 1

To find the number of real number solutions for the equation $x^2-18=0$, we can proceed by solving it step-by-step.

First, set the equation to zero:
$$x^2-18=0$$

Next, add 18 to both sides to isolate $x^2$:
$$x^2=18$$

Now, solve for $x$ by taking the square root of both sides:
$$x=\pm \sqrt{18}$$

The square root of 18 can be simplified as:
$$\sqrt{18}=\sqrt{9\times 2}=\sqrt{9}\times \sqrt{2}=3\sqrt{2}$$

So, the solutions are:
$$x=3\sqrt{2}$$
$$x=-3\sqrt{2}$$

Therefore, there are 2 real number solutions for the equation $x^2-18=0$.

So, the correct answer is:
2