RO divides the rectangle into two congruent right triangles.
The area of the one triangle is equal half area of the rectangle.
Calculate the area of rectangle:

The area of right triangle:

Use the Pythagorean theorem to calculate the length of RO:

The formula of an area of this right triangle is:

Therefore we have the equation:

Answer is x=-2 hope that helps
Answer:

Step-by-step explanation:
If the ruler is divided into 2 equal parts, divide 7 inches by 2
7/2 = 3.5 or 3