What are the solutions of the equation 9x4 – 2x2 – 7 = 0? use u substitution to solve.

U substitution uses the variable "u" as a replacement for another variable. In this case, we will substitute in u for x^2. Since u=x^2 we can now rewrite the equation. 9u^2 -2u -7. This is factored to (u-1)(9u+7). Now put x^2 back in for u. (x^2 -1)(9x^2 +7). Factor again. (x-1)(x+1)(9x^2 + 7). Since 9x^2 + 7 doesn't factor, we don't bother with it any more. The answer is x=1 or x=-1.

Given:

The triangle ABC is reflected over the x-axis.

The distance between point A and A’ is 14.

To find:

The distance between the x-axis and A’.

Solution:

If a figure is reflected across the x-axis then the corresponding parts are mirror image of each other about the x-axis.

It means the distance between A and x-axis is same as the distance between x-axis and A'.

The distance between point A and A’ is 14.

Let d be the distance between the x-axis and A’. Then,

Therefore, the correct option is 1.