Knowing that the area of a square is equivalent the square of its side length, the length of one side can be calculated by taking the square root of the area. The square root of the expression 9q^4r^8s^8 units is equivalent to <span>3q2r4|s3| units. When taking the square root of variables, the power they are raised to is divided by 2.</span>
Answer: 
Step-by-step explanation:
You can use the Method of substitution.
Substitute the equation
into the equation
and then you must solve for the variable x:
Apply Distributive property:

Subtract 12 from both sides of the equation and then add the like terms. Then you get:

Answer:
The area of building c minus the area of building b equals the area of building a might be correct?