Divide your number into perfect square factors. ...
Take the square roots of your perfect square factors. ...
Reduce your answer to simplest terms, if your number doesn't factor perfectly. ...
Estimate, if necessary. ...
Reduce your number to its lowest common factors as a first step.
Step-by-step explanation:

r² (q + bx) = ax - p
qr² + bxr² = ax - p
qr² + p = ax - bxr²
qr² + p = x (a - br²)

It is a function, because you are associating one and exactly one y-value to each x-value.
Hello,
A good method for solving this question is creating an equation to solve for the width of the door.
Let w = the width of the door
Let h = the height of the door
The height (h) is twice the width (2w) and one foot more (+1).
We can make the equation h = 2w + 1
Now, we are given that the height of the door is 7 feet, so h = 7.
We can simply plug in 7 for h in the equation to solve for w.
So, we have h = 2w + 1
7 = 2w + 1
Subtract by 1 on both sides to get:
6 = 2w
Divide by 2 on both sides to get:
w = 3
The width of the door is 3 feet.
However, we should check out answer with the given question to make sure it checks out.
We are given that the height of the door is one foot more than twice its width, and the height of the door is 7 feet.
Twice the width is 6 feet, and one foot more than that is 7 feet. Our answer checks out.
The width of the door is 3 feet.
Hope this helps!