According to the information given in the exercise, the following expression represents the area of the rectangular garden:

And the following expression represents the combined area of the walkway around the rectangular garden and the area of the garden:

You can identify that the word "combined" indicates that that expression was obtained by adding both areas.
Knowing the above, you can set up the following equation:

Where "A" is the area of the walkway around the rectangular garden.
Solving for "A", you get the following expression:

The answer is:
Answer:
1/2(a-4)
Step-by-step explanation:
first blank is 1/2 and second is 4.
In order for an equation to be in standard form, the equation has to be in Ax+By=c form, where A is equal to the coefficient of x and B is equal to the coefficient of y, whereas c is just the constant, or the number in the equation that isn't being multiplied to a variable. In this case, you should first distribute 2y into (x-1), and then you should perform inverse operations on terms on both sides of the equation such that one side of the equation will only have terms with x and y in them and the other side of the equation will only be a numerical value. When the equation is like this, then the equation is in standard form.